ralph_core/

hatless_ralph.rs

//! Hatless Ralph - the constant coordinator.
//!
//! Ralph is always present, cannot be configured away, and acts as a universal fallback.

use crate::config::CoreConfig;
use crate::hat_registry::HatRegistry;
use ralph_proto::Topic;
use std::collections::HashMap;
use std::path::Path;

/// Hatless Ralph - the constant coordinator.
pub struct HatlessRalph {
    completion_promise: String,
    core: CoreConfig,
    hat_topology: Option<HatTopology>,
    /// Event to publish after coordination to start the hat workflow.
    starting_event: Option<String>,
    /// Whether memories mode is enabled.
    /// When enabled, adds tasks CLI instructions alongside scratchpad.
    memories_enabled: bool,
    /// The user's original objective, stored at initialization.
    /// Injected into every prompt so hats always see the goal.
    objective: Option<String>,
    /// Pre-built skill index section for prompt injection.
    /// Set by EventLoop after SkillRegistry is initialized.
    skill_index: String,
    /// Collected robot guidance messages for injection into prompts.
    /// Set by EventLoop before build_prompt(), cleared after injection.
    robot_guidance: Vec<String>,
}

/// Hat topology for multi-hat mode prompt generation.
pub struct HatTopology {
    hats: Vec<HatInfo>,
}

/// Information about a hat that receives an event.
#[derive(Debug, Clone)]
pub struct EventReceiver {
    pub name: String,
    pub description: String,
}

/// Information about a hat for prompt generation.
pub struct HatInfo {
    pub name: String,
    pub description: String,
    pub subscribes_to: Vec<String>,
    pub publishes: Vec<String>,
    pub instructions: String,
    /// Maps each published event to the hats that receive it.
    pub event_receivers: HashMap<String, Vec<EventReceiver>>,
    /// Tools the hat is not allowed to use (prompt-level enforcement).
    pub disallowed_tools: Vec<String>,
}

impl HatInfo {
    /// Generates an Event Publishing Guide section showing what happens when this hat publishes events.
    ///
    /// Returns `None` if the hat doesn't publish any events.
    pub fn event_publishing_guide(&self) -> Option<String> {
        if self.publishes.is_empty() {
            return None;
        }

        let mut guide = String::from(
            "### Event Publishing Guide\n\n\
             You MUST publish exactly ONE event when your work is complete.\n\
             Publishing hands off to the next hat and starts a fresh iteration with clear context.\n\n\
             When you publish:\n",
        );

        for pub_event in &self.publishes {
            let receivers = self.event_receivers.get(pub_event);
            let receiver_text = match receivers {
                Some(r) if !r.is_empty() => r
                    .iter()
                    .map(|recv| {
                        if recv.description.is_empty() {
                            recv.name.clone()
                        } else {
                            format!("{} ({})", recv.name, recv.description)
                        }
                    })
                    .collect::<Vec<_>>()
                    .join(", "),
                _ => "Ralph (coordinates next steps)".to_string(),
            };
            guide.push_str(&format!(
                "- `{}` → Received by: {}\n",
                pub_event, receiver_text
            ));
        }

        Some(guide)
    }
}

impl HatTopology {
    /// Creates topology from registry.
    pub fn from_registry(registry: &HatRegistry) -> Self {
        let hats = registry
            .all()
            .map(|hat| {
                // Compute who receives each event this hat publishes
                let event_receivers: HashMap<String, Vec<EventReceiver>> = hat
                    .publishes
                    .iter()
                    .map(|pub_topic| {
                        let receivers: Vec<EventReceiver> = registry
                            .subscribers(pub_topic)
                            .into_iter()
                            .filter(|h| h.id != hat.id) // Exclude self
                            .map(|h| EventReceiver {
                                name: h.name.clone(),
                                description: h.description.clone(),
                            })
                            .collect();
                        (pub_topic.as_str().to_string(), receivers)
                    })
                    .collect();

                let disallowed_tools = registry
                    .get_config(&hat.id)
                    .map(|c| c.disallowed_tools.clone())
                    .unwrap_or_default();

                HatInfo {
                    name: hat.name.clone(),
                    description: hat.description.clone(),
                    subscribes_to: hat
                        .subscriptions
                        .iter()
                        .map(|t| t.as_str().to_string())
                        .collect(),
                    publishes: hat
                        .publishes
                        .iter()
                        .map(|t| t.as_str().to_string())
                        .collect(),
                    instructions: hat.instructions.clone(),
                    event_receivers,
                    disallowed_tools,
                }
            })
            .collect();

        Self { hats }
    }
}

impl HatlessRalph {
    /// Creates a new HatlessRalph.
    ///
    /// # Arguments
    /// * `completion_promise` - Event topic that signals loop completion
    /// * `core` - Core configuration (scratchpad, specs_dir, guardrails)
    /// * `registry` - Hat registry for topology generation
    /// * `starting_event` - Optional event to publish after coordination to start hat workflow
    pub fn new(
        completion_promise: impl Into<String>,
        core: CoreConfig,
        registry: &HatRegistry,
        starting_event: Option<String>,
    ) -> Self {
        let hat_topology = if registry.is_empty() {
            None
        } else {
            Some(HatTopology::from_registry(registry))
        };

        Self {
            completion_promise: completion_promise.into(),
            core,
            hat_topology,
            starting_event,
            memories_enabled: false, // Default: scratchpad-only mode
            objective: None,
            skill_index: String::new(),
            robot_guidance: Vec::new(),
        }
    }

    /// Sets whether memories mode is enabled.
    ///
    /// When enabled, adds tasks CLI instructions alongside scratchpad.
    /// Scratchpad is always included regardless of this setting.
    pub fn with_memories_enabled(mut self, enabled: bool) -> Self {
        self.memories_enabled = enabled;
        self
    }

    /// Sets the pre-built skill index for prompt injection.
    ///
    /// The skill index is a compact table of available skills that appears
    /// between GUARDRAILS and OBJECTIVE in the prompt.
    pub fn with_skill_index(mut self, index: String) -> Self {
        self.skill_index = index;
        self
    }

    /// Stores the user's original objective so it persists across all iterations.
    ///
    /// Called once during initialization. The objective is injected into every
    /// prompt regardless of which hat is active, ensuring intermediate hats
    /// (test_writer, implementer, refactorer) always see the goal.
    pub fn set_objective(&mut self, objective: String) {
        self.objective = Some(objective);
    }

    /// Sets robot guidance messages collected from `human.guidance` events.
    ///
    /// Called by `EventLoop::build_prompt()` before `HatlessRalph::build_prompt()`.
    /// Multiple guidance messages are squashed into a numbered list and injected
    /// as a `## ROBOT GUIDANCE` section in the prompt.
    pub fn set_robot_guidance(&mut self, guidance: Vec<String>) {
        self.robot_guidance = guidance;
    }

    /// Clears stored robot guidance after it has been injected into a prompt.
    ///
    /// Called by `EventLoop::build_prompt()` after `HatlessRalph::build_prompt()`.
    pub fn clear_robot_guidance(&mut self) {
        self.robot_guidance.clear();
    }

    /// Collects robot guidance and returns the formatted prompt section.
    ///
    /// Squashes multiple guidance messages into a numbered list format.
    /// Returns an empty string if no guidance is pending.
    fn collect_robot_guidance(&self) -> String {
        if self.robot_guidance.is_empty() {
            return String::new();
        }

        let mut section = String::from("## ROBOT GUIDANCE\n\n");

        if self.robot_guidance.len() == 1 {
            section.push_str(&self.robot_guidance[0]);
        } else {
            for (i, guidance) in self.robot_guidance.iter().enumerate() {
                section.push_str(&format!("{}. {}\n", i + 1, guidance));
            }
        }

        section.push_str("\n\n");

        section
    }

    /// Builds Ralph's prompt with filtered instructions for only active hats.
    ///
    /// This method reduces token usage by including instructions only for hats
    /// that are currently triggered by pending events, while still showing the
    /// full hat topology table for context.
    ///
    /// For solo mode (no hats), pass an empty slice: `&[]`
    pub fn build_prompt(&self, context: &str, active_hats: &[&ralph_proto::Hat]) -> String {
        let mut prompt = self.core_prompt();

        // Inject skill index between GUARDRAILS and OBJECTIVE
        if !self.skill_index.is_empty() {
            prompt.push_str(&self.skill_index);
            prompt.push('\n');
        }

        // Add prominent OBJECTIVE section first (stored at initialization, persists across all iterations)
        if let Some(ref obj) = self.objective {
            prompt.push_str(&self.objective_section(obj));
        }

        // Inject robot guidance (collected from human.guidance events, cleared after injection)
        let guidance = self.collect_robot_guidance();
        if !guidance.is_empty() {
            prompt.push_str(&guidance);
        }

        // Include pending events BEFORE workflow so Ralph sees the task first
        if !context.trim().is_empty() {
            prompt.push_str("## PENDING EVENTS\n\n");
            prompt.push_str("You MUST handle these events in this iteration:\n\n");
            prompt.push_str(context);
            prompt.push_str("\n\n");
        }

        // Check if any active hat has custom instructions
        // If so, skip the generic workflow - the hat's instructions ARE the workflow
        let has_custom_workflow = active_hats
            .iter()
            .any(|h| !h.instructions.trim().is_empty());

        if !has_custom_workflow {
            prompt.push_str(&self.workflow_section());
        }

        if let Some(topology) = &self.hat_topology {
            prompt.push_str(&self.hats_section(topology, active_hats));
        }

        prompt.push_str(&self.event_writing_section());

        // Only show completion instructions when Ralph is coordinating (no active hat).
        // Hats should publish events and stop — only Ralph decides when the loop is done.
        if active_hats.is_empty() {
            prompt.push_str(&self.done_section(self.objective.as_deref()));
        }

        prompt
    }

    /// Generates the OBJECTIVE section - the primary goal Ralph must achieve.
    fn objective_section(&self, objective: &str) -> String {
        format!(
            r"## OBJECTIVE

**This is your primary goal. All work must advance this objective.**

> {objective}

You MUST keep this objective in mind throughout the iteration.
You MUST NOT get distracted by workflow mechanics — they serve this goal.

",
            objective = objective
        )
    }

    /// Always returns true - Ralph handles all events as fallback.
    pub fn should_handle(&self, _topic: &Topic) -> bool {
        true
    }

    /// Checks if this is a fresh start (starting_event set, no scratchpad).
    ///
    /// Used to enable fast path delegation that skips the PLAN step
    /// when immediate delegation to specialized hats is appropriate.
    fn is_fresh_start(&self) -> bool {
        // Fast path only applies when starting_event is configured
        if self.starting_event.is_none() {
            return false;
        }

        // Check if scratchpad exists
        let path = Path::new(&self.core.scratchpad);
        !path.exists()
    }

    fn core_prompt(&self) -> String {
        // Adapt guardrails based on whether scratchpad or memories mode is active
        let guardrails = self
            .core
            .guardrails
            .iter()
            .enumerate()
            .map(|(i, g)| {
                // Replace scratchpad reference with memories reference when memories are enabled
                let guardrail = if self.memories_enabled && g.contains("scratchpad is memory") {
                    g.replace(
                        "scratchpad is memory",
                        "save learnings to memories for next time",
                    )
                } else {
                    g.clone()
                };
                format!("{}. {guardrail}", 999 + i)
            })
            .collect::<Vec<_>>()
            .join("\n");

        let mut prompt = if self.memories_enabled {
            r"
### 0a. ORIENTATION
You are Ralph. You are running in a loop. You have fresh context each iteration.
You MUST complete only one atomic task for the overall objective. Leave work for future iterations.

**First thing every iteration:**
1. Review your `<scratchpad>` (auto-injected above) for context on your thinking
2. Review your `<ready-tasks>` (auto-injected above) to see what work exists
3. If tasks exist, pick one. If not, create them from your plan.
"
        } else {
            r"
### 0a. ORIENTATION
You are Ralph. You are running in a loop. You have fresh context each iteration.
You MUST complete only one atomic task for the overall objective. Leave work for future iterations.
"
        }
        .to_string();

        // SCRATCHPAD section - ALWAYS present
        prompt.push_str(&format!(
            r"### 0b. SCRATCHPAD
`{scratchpad}` is your thinking journal for THIS objective.
Its content is auto-injected in `<scratchpad>` tags at the top of your context each iteration.

**Always append** new entries to the end of the file (most recent = bottom).

**Use for:**
- Current understanding and reasoning
- Analysis notes and decisions
- Plan narrative (the 'why' behind your approach)

**Do NOT use for:**
- Tracking what tasks exist or their status (use `ralph tools task`)
- Checklists or todo lists (use `ralph tools task add`)

",
            scratchpad = self.core.scratchpad,
        ));

        // TASKS section removed — now injected via skills auto-injection pipeline
        // (see EventLoop::inject_memories_and_tools_skill)
        // TASK BREAKDOWN guidance moved into ralph-tools.md

        // Add state management guidance
        prompt.push_str(&format!(
            "### STATE MANAGEMENT\n\n\
**Tasks** (`ralph tools task`) — What needs to be done:\n\
- Work items, their status, priorities, and dependencies\n\
- Source of truth for progress across iterations\n\
- Auto-injected in `<ready-tasks>` tags at the top of your context\n\
\n\
**Scratchpad** (`{scratchpad}`) — Your thinking:\n\
- Current understanding and reasoning\n\
- Analysis notes, decisions, plan narrative\n\
- NOT for checklists or status tracking\n\
\n\
**Memories** (`.ralph/agent/memories.md`) — Persistent learning:\n\
- Codebase patterns and conventions\n\
- Architectural decisions and rationale\n\
- Recurring problem solutions\n\
\n\
**Context Files** (`.ralph/agent/*.md`) — Research artifacts:\n\
- Analysis and temporary notes\n\
- Read when relevant\n\
\n\
**Rule:** Work items go in tasks. Thinking goes in scratchpad. Learnings go in memories.\n\
\n",
            scratchpad = self.core.scratchpad,
        ));

        // List available context files in .ralph/agent/
        if let Ok(entries) = std::fs::read_dir(".ralph/agent") {
            let md_files: Vec<String> = entries
                .filter_map(|e| e.ok())
                .filter_map(|e| {
                    let path = e.path();
                    if path.extension().and_then(|s| s.to_str()) == Some("md")
                        && path.file_name().and_then(|s| s.to_str()) != Some("memories.md")
                    {
                        path.file_name()
                            .and_then(|s| s.to_str())
                            .map(|s| s.to_string())
                    } else {
                        None
                    }
                })
                .collect();

            if !md_files.is_empty() {
                prompt.push_str("### AVAILABLE CONTEXT FILES\n\n");
                prompt.push_str(
                    "Context files in `.ralph/agent/` (read if relevant to current work):\n",
                );
                for file in md_files {
                    prompt.push_str(&format!("- `.ralph/agent/{}`\n", file));
                }
                prompt.push('\n');
            }
        }

        prompt.push_str(&format!(
            r"### GUARDRAILS
{guardrails}

",
            guardrails = guardrails,
        ));

        prompt
    }

    fn workflow_section(&self) -> String {
        // Different workflow for solo mode vs multi-hat mode
        if self.hat_topology.is_some() {
            // Check for fast path: starting_event set AND no scratchpad
            if self.is_fresh_start() {
                // Fast path: immediate delegation without planning
                return format!(
                    r"## WORKFLOW

**FAST PATH**: You MUST publish `{}` immediately to start the hat workflow.
You MUST NOT plan or analyze — delegate now.

",
                    self.starting_event.as_ref().unwrap()
                );
            }

            // Multi-hat mode: Ralph coordinates and delegates
            if self.memories_enabled {
                // Memories mode: reference both scratchpad AND tasks CLI
                format!(
                    r"## WORKFLOW

### 1. PLAN
You MUST update `{scratchpad}` with your understanding and plan.
You MUST create tasks with `ralph tools task add` for each work item (check `<ready-tasks>` first to avoid duplicates).

### 2. DELEGATE
You MUST publish exactly ONE event to hand off to specialized hats.
You MUST NOT do implementation work — delegation is your only job.

",
                    scratchpad = self.core.scratchpad
                )
            } else {
                // Scratchpad-only mode (legacy)
                format!(
                    r"## WORKFLOW

### 1. PLAN
You MUST update `{scratchpad}` with prioritized tasks to complete the objective end-to-end.

### 2. DELEGATE
You MUST publish exactly ONE event to hand off to specialized hats.
You MUST NOT do implementation work — delegation is your only job.

",
                    scratchpad = self.core.scratchpad
                )
            }
        } else {
            // Solo mode: Ralph does everything
            if self.memories_enabled {
                // Memories mode: reference both scratchpad AND tasks CLI
                format!(
                    r"## WORKFLOW

### 1. Study the prompt.
You MUST study, explore, and research what needs to be done.

### 2. PLAN
You MUST update `{scratchpad}` with your understanding and plan.
You MUST create tasks with `ralph tools task add` for each work item (check `<ready-tasks>` first to avoid duplicates).

### 3. IMPLEMENT
You MUST pick exactly ONE task from `<ready-tasks>` to implement.

### 4. VERIFY & COMMIT
You MUST run tests and verify the implementation works.
You MUST commit after verification passes - one commit per task.
You SHOULD run `git diff --cached` to review staged changes before committing.
You MUST close the task with `ralph tools task close <id>` AFTER commit.
You SHOULD save learnings to memories with `ralph tools memory add`.
You MUST update scratchpad with what you learned (tasks track what remains).

### 5. EXIT
You MUST exit after completing ONE task.

",
                    scratchpad = self.core.scratchpad
                )
            } else {
                // Scratchpad-only mode (legacy)
                format!(
                    r"## WORKFLOW

### 1. Study the prompt.
You MUST study, explore, and research what needs to be done.
You MAY use parallel subagents (up to 10) for searches.

### 2. PLAN
You MUST update `{scratchpad}` with prioritized tasks to complete the objective end-to-end.

### 3. IMPLEMENT
You MUST pick exactly ONE task to implement.
You MUST NOT use more than 1 subagent for build/tests.

### 4. COMMIT
You MUST commit after completing each atomic unit of work.
You MUST capture the why, not just the what.
You SHOULD run `git diff` before committing to review changes.
You MUST mark the task `[x]` in scratchpad when complete.

### 5. REPEAT
You MUST continue until all tasks are `[x]` or `[~]`.

",
                    scratchpad = self.core.scratchpad
                )
            }
        }
    }

    fn hats_section(&self, topology: &HatTopology, active_hats: &[&ralph_proto::Hat]) -> String {
        let mut section = String::new();

        // When a specific hat is active, skip the topology overview (table + Mermaid)
        // The hat just needs its instructions and publishing guide
        if active_hats.is_empty() {
            // Ralph is coordinating - show full topology for delegation decisions
            section.push_str("## HATS\n\nDelegate via events.\n\n");

            // Include starting_event instruction if configured
            if let Some(ref starting_event) = self.starting_event {
                section.push_str(&format!(
                    "**After coordination, publish `{}` to start the workflow.**\n\n",
                    starting_event
                ));
            }

            // Derive Ralph's triggers and publishes from topology
            // Ralph triggers on: task.start + all hats' publishes (results Ralph handles)
            // Ralph publishes: all hats' subscribes_to (events Ralph can emit to delegate)
            let mut ralph_triggers: Vec<&str> = vec!["task.start"];
            let mut ralph_publishes: Vec<&str> = Vec::new();

            for hat in &topology.hats {
                for pub_event in &hat.publishes {
                    if !ralph_triggers.contains(&pub_event.as_str()) {
                        ralph_triggers.push(pub_event.as_str());
                    }
                }
                for sub_event in &hat.subscribes_to {
                    if !ralph_publishes.contains(&sub_event.as_str()) {
                        ralph_publishes.push(sub_event.as_str());
                    }
                }
            }

            // Build hat table with Description column
            section.push_str("| Hat | Triggers On | Publishes | Description |\n");
            section.push_str("|-----|-------------|----------|-------------|\n");

            // Add Ralph coordinator row first
            section.push_str(&format!(
                "| Ralph | {} | {} | Coordinates workflow, delegates to specialized hats |\n",
                ralph_triggers.join(", "),
                ralph_publishes.join(", ")
            ));

            // Add all other hats
            for hat in &topology.hats {
                let subscribes = hat.subscribes_to.join(", ");
                let publishes = hat.publishes.join(", ");
                section.push_str(&format!(
                    "| {} | {} | {} | {} |\n",
                    hat.name, subscribes, publishes, hat.description
                ));
            }

            section.push('\n');

            // Generate Mermaid topology diagram
            section.push_str(&self.generate_mermaid_diagram(topology, &ralph_publishes));
            section.push('\n');

            // Add explicit constraint listing valid events Ralph can publish
            if !ralph_publishes.is_empty() {
                section.push_str(&format!(
                    "**CONSTRAINT:** You MUST only publish events from this list: `{}`\n\
                     Publishing other events will have no effect - no hat will receive them.\n\n",
                    ralph_publishes.join("`, `")
                ));
            }

            // Validate topology and log warnings for unreachable hats
            self.validate_topology_reachability(topology);
        } else {
            // Specific hat(s) active - minimal section with just instructions + guide
            section.push_str("## ACTIVE HAT\n\n");

            for active_hat in active_hats {
                // Find matching HatInfo from topology to access event_receivers
                let hat_info = topology.hats.iter().find(|h| h.name == active_hat.name);

                if !active_hat.instructions.trim().is_empty() {
                    section.push_str(&format!("### {} Instructions\n\n", active_hat.name));
                    section.push_str(&active_hat.instructions);
                    if !active_hat.instructions.ends_with('\n') {
                        section.push('\n');
                    }
                    section.push('\n');
                }

                // Add Event Publishing Guide after instructions (if hat publishes events)
                if let Some(guide) = hat_info.and_then(|info| info.event_publishing_guide()) {
                    section.push_str(&guide);
                    section.push('\n');
                }

                // Add Tool Restrictions section (prompt-level enforcement)
                if let Some(info) = hat_info
                    && !info.disallowed_tools.is_empty()
                {
                    section.push_str("### TOOL RESTRICTIONS\n\n");
                    section.push_str("You MUST NOT use these tools in this hat:\n");
                    for tool in &info.disallowed_tools {
                        section.push_str(&format!("- **{}** — blocked for this hat\n", tool));
                    }
                    section.push_str(
                        "\nUsing a restricted tool is a scope violation. \
                         File modifications are audited after each iteration.\n\n",
                    );
                }
            }
        }

        section
    }

    /// Generates a Mermaid flowchart showing event flow between hats.
    fn generate_mermaid_diagram(&self, topology: &HatTopology, ralph_publishes: &[&str]) -> String {
        // Pre-compute sanitized Mermaid node IDs (strip emojis/special chars)
        let node_ids: std::collections::HashMap<&str, String> = topology
            .hats
            .iter()
            .map(|h| {
                let id = h
                    .name
                    .chars()
                    .filter(|c| c.is_alphanumeric())
                    .collect::<String>();
                (h.name.as_str(), id)
            })
            .collect();

        let mut diagram = String::from("```mermaid\nflowchart LR\n");

        // Entry point: task.start -> Ralph
        diagram.push_str("    task.start((task.start)) --> Ralph\n");

        // Ralph -> hats (via ralph_publishes which are hat triggers)
        for hat in &topology.hats {
            let node_id = &node_ids[hat.name.as_str()];
            for trigger in &hat.subscribes_to {
                if ralph_publishes.contains(&trigger.as_str()) {
                    if node_id == &hat.name {
                        diagram.push_str(&format!("    Ralph -->|{}| {}\n", trigger, hat.name));
                    } else {
                        diagram.push_str(&format!(
                            "    Ralph -->|{}| {}[{}]\n",
                            trigger, node_id, hat.name
                        ));
                    }
                }
            }
        }

        // Hats -> Ralph (via hat publishes)
        for hat in &topology.hats {
            let node_id = &node_ids[hat.name.as_str()];
            for pub_event in &hat.publishes {
                diagram.push_str(&format!("    {} -->|{}| Ralph\n", node_id, pub_event));
            }
        }

        // Hat -> Hat connections (when one hat publishes what another triggers on)
        for source_hat in &topology.hats {
            let source_id = &node_ids[source_hat.name.as_str()];
            for pub_event in &source_hat.publishes {
                for target_hat in &topology.hats {
                    if target_hat.name != source_hat.name
                        && target_hat.subscribes_to.contains(pub_event)
                    {
                        let target_id = &node_ids[target_hat.name.as_str()];
                        diagram.push_str(&format!(
                            "    {} -->|{}| {}\n",
                            source_id, pub_event, target_id
                        ));
                    }
                }
            }
        }

        diagram.push_str("```\n");
        diagram
    }

    /// Validates that all hats are reachable from task.start.
    /// Logs warnings for unreachable hats but doesn't fail.
    fn validate_topology_reachability(&self, topology: &HatTopology) {
        use std::collections::HashSet;
        use tracing::warn;

        // Collect all events that are published (reachable)
        let mut reachable_events: HashSet<&str> = HashSet::new();
        reachable_events.insert("task.start");

        // Ralph publishes all hat triggers, so add those
        for hat in &topology.hats {
            for trigger in &hat.subscribes_to {
                reachable_events.insert(trigger.as_str());
            }
        }

        // Now add all events published by hats (they become reachable after hat runs)
        for hat in &topology.hats {
            for pub_event in &hat.publishes {
                reachable_events.insert(pub_event.as_str());
            }
        }

        // Check each hat's triggers - warn if none of them are reachable
        for hat in &topology.hats {
            let hat_reachable = hat
                .subscribes_to
                .iter()
                .any(|t| reachable_events.contains(t.as_str()));
            if !hat_reachable {
                warn!(
                    hat = %hat.name,
                    triggers = ?hat.subscribes_to,
                    "Hat has triggers that are never published - it may be unreachable"
                );
            }
        }
    }

    fn event_writing_section(&self) -> String {
        // Always use scratchpad for detailed output (scratchpad is always present)
        let detailed_output_hint = format!(
            "You SHOULD write detailed output to `{}` and emit only a brief event.",
            self.core.scratchpad
        );

        format!(
            r#"## EVENT WRITING

Events are routing signals, not data transport. You SHOULD keep payloads brief.

You MUST use `ralph emit` to write events (handles JSON escaping correctly):
```bash
ralph emit "build.done" "tests: pass, lint: pass, typecheck: pass, audit: pass, coverage: pass"
ralph emit "review.done" --json '{{"status": "approved", "issues": 0}}'
```

You MUST NOT use echo/cat to write events because shell escaping breaks JSON.

{detailed_output_hint}

**Constraints:**
- You MUST stop working after publishing an event because a new iteration will start with fresh context
- You MUST NOT continue with additional work after publishing because the next iteration handles it with the appropriate hat persona
"#,
            detailed_output_hint = detailed_output_hint
        )
    }

    fn done_section(&self, objective: Option<&str>) -> String {
        let mut section = format!(
            r"## DONE

You MUST emit a completion event `{}` when the objective is complete and all tasks are done.
You MUST use `ralph emit` (stdout text does NOT end the loop).
",
            self.completion_promise
        );

        // Add task verification when memories/tasks mode is enabled
        if self.memories_enabled {
            section.push_str(
                r"
**Before declaring completion:**
1. Run `ralph tools task ready` to check for open tasks
2. If any tasks are open, complete them first
3. Only emit the completion event when YOUR tasks are all closed

Tasks from other parallel loops are filtered out automatically. You only need to verify tasks YOU created for THIS objective are complete.

You MUST NOT emit the completion event while tasks remain open.
",
            );
        }

        // Reinforce the objective at the end to bookend the prompt
        if let Some(obj) = objective {
            section.push_str(&format!(
                r"
**Remember your objective:**
> {}

You MUST NOT declare completion until this objective is fully satisfied.
",
                obj
            ));
        }

        section
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::config::RalphConfig;

    #[test]
    fn test_prompt_without_hats() {
        let config = RalphConfig::default();
        let registry = HatRegistry::new(); // Empty registry
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // Identity with RFC2119 style
        assert!(prompt.contains(
            "You are Ralph. You are running in a loop. You have fresh context each iteration."
        ));

        // Numbered orientation phases (RFC2119)
        assert!(prompt.contains("### 0a. ORIENTATION"));
        assert!(prompt.contains("MUST complete only one atomic task"));

        // Scratchpad section with auto-inject and append instructions
        assert!(prompt.contains("### 0b. SCRATCHPAD"));
        assert!(prompt.contains("auto-injected"));
        assert!(prompt.contains("**Always append**"));

        // Workflow with numbered steps (solo mode) using RFC2119
        assert!(prompt.contains("## WORKFLOW"));
        assert!(prompt.contains("### 1. Study the prompt"));
        assert!(prompt.contains("You MAY use parallel subagents (up to 10)"));
        assert!(prompt.contains("### 2. PLAN"));
        assert!(prompt.contains("### 3. IMPLEMENT"));
        assert!(prompt.contains("You MUST NOT use more than 1 subagent for build/tests"));
        assert!(prompt.contains("### 4. COMMIT"));
        assert!(prompt.contains("You MUST capture the why"));
        assert!(prompt.contains("### 5. REPEAT"));

        // Should NOT have hats section when no hats
        assert!(!prompt.contains("## HATS"));

        // Event writing and completion using RFC2119
        assert!(prompt.contains("## EVENT WRITING"));
        assert!(prompt.contains("You MUST use `ralph emit`"));
        assert!(prompt.contains("You MUST NOT use echo/cat"));
        assert!(prompt.contains("LOOP_COMPLETE"));
    }

    #[test]
    fn test_prompt_with_hats() {
        // Test multi-hat mode WITHOUT starting_event (no fast path)
        let yaml = r#"
hats:
  planner:
    name: "Planner"
    triggers: ["planning.start", "build.done", "build.blocked"]
    publishes: ["build.task"]
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done", "build.blocked"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        // Note: No starting_event - tests normal multi-hat workflow (not fast path)
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // Identity with RFC2119 style
        assert!(prompt.contains(
            "You are Ralph. You are running in a loop. You have fresh context each iteration."
        ));

        // Orientation phases
        assert!(prompt.contains("### 0a. ORIENTATION"));
        assert!(prompt.contains("### 0b. SCRATCHPAD"));

        // Multi-hat workflow: PLAN + DELEGATE, not IMPLEMENT (RFC2119)
        assert!(prompt.contains("## WORKFLOW"));
        assert!(prompt.contains("### 1. PLAN"));
        assert!(
            prompt.contains("### 2. DELEGATE"),
            "Multi-hat mode should have DELEGATE step"
        );
        assert!(
            !prompt.contains("### 3. IMPLEMENT"),
            "Multi-hat mode should NOT tell Ralph to implement"
        );
        assert!(
            prompt.contains("You MUST stop working after publishing"),
            "Should explicitly tell Ralph to stop after publishing event"
        );

        // Hats section when hats are defined
        assert!(prompt.contains("## HATS"));
        assert!(prompt.contains("Delegate via events"));
        assert!(prompt.contains("| Hat | Triggers On | Publishes |"));

        // Event writing and completion
        assert!(prompt.contains("## EVENT WRITING"));
        assert!(prompt.contains("LOOP_COMPLETE"));
    }

    #[test]
    fn test_should_handle_always_true() {
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        assert!(ralph.should_handle(&Topic::new("any.topic")));
        assert!(ralph.should_handle(&Topic::new("build.task")));
        assert!(ralph.should_handle(&Topic::new("unknown.event")));
    }

    #[test]
    fn test_rfc2119_patterns_present() {
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // Key RFC2119 language patterns
        assert!(
            prompt.contains("You MUST study"),
            "Should use RFC2119 MUST with 'study' verb"
        );
        assert!(
            prompt.contains("You MUST complete only one atomic task"),
            "Should have RFC2119 MUST complete atomic task constraint"
        );
        assert!(
            prompt.contains("You MAY use parallel subagents"),
            "Should mention parallel subagents with MAY"
        );
        assert!(
            prompt.contains("You MUST NOT use more than 1 subagent"),
            "Should limit to 1 subagent for builds with MUST NOT"
        );
        assert!(
            prompt.contains("You MUST capture the why"),
            "Should emphasize 'why' in commits with MUST"
        );

        // Numbered guardrails (999+)
        assert!(
            prompt.contains("### GUARDRAILS"),
            "Should have guardrails section"
        );
        assert!(
            prompt.contains("999."),
            "Guardrails should use high numbers"
        );
    }

    #[test]
    fn test_scratchpad_format_documented() {
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // Auto-injection and append instructions are documented
        assert!(prompt.contains("auto-injected"));
        assert!(prompt.contains("**Always append**"));
    }

    #[test]
    fn test_starting_event_in_prompt() {
        // When starting_event is configured, prompt should include delegation instruction
        let yaml = r#"
hats:
  tdd_writer:
    name: "TDD Writer"
    triggers: ["tdd.start"]
    publishes: ["test.written"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new(
            "LOOP_COMPLETE",
            config.core.clone(),
            &registry,
            Some("tdd.start".to_string()),
        );

        let prompt = ralph.build_prompt("", &[]);

        // Should include delegation instruction
        assert!(
            prompt.contains("After coordination, publish `tdd.start` to start the workflow"),
            "Prompt should include starting_event delegation instruction"
        );
    }

    #[test]
    fn test_no_starting_event_instruction_when_none() {
        // When starting_event is None, no delegation instruction should appear
        let yaml = r#"
hats:
  some_hat:
    name: "Some Hat"
    triggers: ["some.event"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // Should NOT include delegation instruction
        assert!(
            !prompt.contains("After coordination, publish"),
            "Prompt should NOT include starting_event delegation when None"
        );
    }

    #[test]
    fn test_hat_instructions_propagated_to_prompt() {
        // When a hat has instructions defined in config,
        // those instructions should appear in the generated prompt
        let yaml = r#"
hats:
  tdd_writer:
    name: "TDD Writer"
    triggers: ["tdd.start"]
    publishes: ["test.written"]
    instructions: |
      You are a Test-Driven Development specialist.
      Always write failing tests before implementation.
      Focus on edge cases and error handling.
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new(
            "LOOP_COMPLETE",
            config.core.clone(),
            &registry,
            Some("tdd.start".to_string()),
        );

        // Get the tdd_writer hat as active to see its instructions
        let tdd_writer = registry
            .get(&ralph_proto::HatId::new("tdd_writer"))
            .unwrap();
        let prompt = ralph.build_prompt("", &[tdd_writer]);

        // Instructions should appear in the prompt
        assert!(
            prompt.contains("### TDD Writer Instructions"),
            "Prompt should include hat instructions section header"
        );
        assert!(
            prompt.contains("Test-Driven Development specialist"),
            "Prompt should include actual instructions content"
        );
        assert!(
            prompt.contains("Always write failing tests"),
            "Prompt should include full instructions"
        );
    }

    #[test]
    fn test_empty_instructions_not_rendered() {
        // When a hat has empty/no instructions, no instructions section should appear
        let yaml = r#"
hats:
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // No instructions section should appear for hats without instructions
        assert!(
            !prompt.contains("### Builder Instructions"),
            "Prompt should NOT include instructions section for hat with empty instructions"
        );
    }

    #[test]
    fn test_multiple_hats_with_instructions() {
        // When multiple hats have instructions, each should have its own section
        let yaml = r#"
hats:
  planner:
    name: "Planner"
    triggers: ["planning.start"]
    publishes: ["build.task"]
    instructions: "Plan carefully before implementation."
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done"]
    instructions: "Focus on clean, testable code."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // Get both hats as active to see their instructions
        let planner = registry.get(&ralph_proto::HatId::new("planner")).unwrap();
        let builder = registry.get(&ralph_proto::HatId::new("builder")).unwrap();
        let prompt = ralph.build_prompt("", &[planner, builder]);

        // Both hats' instructions should appear
        assert!(
            prompt.contains("### Planner Instructions"),
            "Prompt should include Planner instructions section"
        );
        assert!(
            prompt.contains("Plan carefully before implementation"),
            "Prompt should include Planner instructions content"
        );
        assert!(
            prompt.contains("### Builder Instructions"),
            "Prompt should include Builder instructions section"
        );
        assert!(
            prompt.contains("Focus on clean, testable code"),
            "Prompt should include Builder instructions content"
        );
    }

    #[test]
    fn test_fast_path_with_starting_event() {
        // When starting_event is configured AND scratchpad doesn't exist,
        // should use fast path (skip PLAN step)
        let yaml = r#"
core:
  scratchpad: "/nonexistent/path/scratchpad.md"
hats:
  tdd_writer:
    name: "TDD Writer"
    triggers: ["tdd.start"]
    publishes: ["test.written"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new(
            "LOOP_COMPLETE",
            config.core.clone(),
            &registry,
            Some("tdd.start".to_string()),
        );

        let prompt = ralph.build_prompt("", &[]);

        // Should use fast path - immediate delegation with RFC2119
        assert!(
            prompt.contains("FAST PATH"),
            "Prompt should indicate fast path when starting_event set and no scratchpad"
        );
        assert!(
            prompt.contains("You MUST publish `tdd.start` immediately"),
            "Prompt should instruct immediate event publishing with MUST"
        );
        assert!(
            !prompt.contains("### 1. PLAN"),
            "Fast path should skip PLAN step"
        );
    }

    #[test]
    fn test_events_context_included_in_prompt() {
        // Given a non-empty events context
        // When build_prompt(context) is called
        // Then the prompt contains ## PENDING EVENTS section with the context
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let events_context = r"[task.start] User's task: Review this code for security vulnerabilities
[build.done] Build completed successfully";

        let prompt = ralph.build_prompt(events_context, &[]);

        assert!(
            prompt.contains("## PENDING EVENTS"),
            "Prompt should contain PENDING EVENTS section"
        );
        assert!(
            prompt.contains("Review this code for security vulnerabilities"),
            "Prompt should contain the user's task"
        );
        assert!(
            prompt.contains("Build completed successfully"),
            "Prompt should contain all events from context"
        );
    }

    #[test]
    fn test_empty_context_no_pending_events_section() {
        // Given an empty events context
        // When build_prompt("") is called
        // Then no PENDING EVENTS section appears
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            !prompt.contains("## PENDING EVENTS"),
            "Empty context should not produce PENDING EVENTS section"
        );
    }

    #[test]
    fn test_whitespace_only_context_no_pending_events_section() {
        // Given a whitespace-only events context
        // When build_prompt is called
        // Then no PENDING EVENTS section appears
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("   \n\t  ", &[]);

        assert!(
            !prompt.contains("## PENDING EVENTS"),
            "Whitespace-only context should not produce PENDING EVENTS section"
        );
    }

    #[test]
    fn test_events_section_before_workflow() {
        // Given events context with a task
        // When prompt is built
        // Then ## PENDING EVENTS appears BEFORE ## WORKFLOW
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let events_context = "[task.start] Implement feature X";
        let prompt = ralph.build_prompt(events_context, &[]);

        let events_pos = prompt
            .find("## PENDING EVENTS")
            .expect("Should have PENDING EVENTS");
        let workflow_pos = prompt.find("## WORKFLOW").expect("Should have WORKFLOW");

        assert!(
            events_pos < workflow_pos,
            "PENDING EVENTS ({}) should come before WORKFLOW ({})",
            events_pos,
            workflow_pos
        );
    }

    // === Phase 3: Filtered Hat Instructions Tests ===

    #[test]
    fn test_only_active_hat_instructions_included() {
        // Scenario 4 from plan.md: Only active hat instructions included in prompt
        let yaml = r#"
hats:
  security_reviewer:
    name: "Security Reviewer"
    triggers: ["review.security"]
    instructions: "Review code for security vulnerabilities."
  architecture_reviewer:
    name: "Architecture Reviewer"
    triggers: ["review.architecture"]
    instructions: "Review system design and architecture."
  correctness_reviewer:
    name: "Correctness Reviewer"
    triggers: ["review.correctness"]
    instructions: "Review logic and correctness."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // Get active hats - only security_reviewer is active
        let security_hat = registry
            .get(&ralph_proto::HatId::new("security_reviewer"))
            .unwrap();
        let active_hats = vec![security_hat];

        let prompt = ralph.build_prompt("Event: review.security - Check auth", &active_hats);

        // Should contain ONLY security_reviewer instructions
        assert!(
            prompt.contains("### Security Reviewer Instructions"),
            "Should include Security Reviewer instructions section"
        );
        assert!(
            prompt.contains("Review code for security vulnerabilities"),
            "Should include Security Reviewer instructions content"
        );

        // Should NOT contain other hats' instructions
        assert!(
            !prompt.contains("### Architecture Reviewer Instructions"),
            "Should NOT include Architecture Reviewer instructions"
        );
        assert!(
            !prompt.contains("Review system design and architecture"),
            "Should NOT include Architecture Reviewer instructions content"
        );
        assert!(
            !prompt.contains("### Correctness Reviewer Instructions"),
            "Should NOT include Correctness Reviewer instructions"
        );
    }

    #[test]
    fn test_multiple_active_hats_all_included() {
        // Scenario 6 from plan.md: Multiple active hats includes all instructions
        let yaml = r#"
hats:
  security_reviewer:
    name: "Security Reviewer"
    triggers: ["review.security"]
    instructions: "Review code for security vulnerabilities."
  architecture_reviewer:
    name: "Architecture Reviewer"
    triggers: ["review.architecture"]
    instructions: "Review system design and architecture."
  correctness_reviewer:
    name: "Correctness Reviewer"
    triggers: ["review.correctness"]
    instructions: "Review logic and correctness."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // Get active hats - both security_reviewer and architecture_reviewer are active
        let security_hat = registry
            .get(&ralph_proto::HatId::new("security_reviewer"))
            .unwrap();
        let arch_hat = registry
            .get(&ralph_proto::HatId::new("architecture_reviewer"))
            .unwrap();
        let active_hats = vec![security_hat, arch_hat];

        let prompt = ralph.build_prompt("Events", &active_hats);

        // Should contain BOTH active hats' instructions
        assert!(
            prompt.contains("### Security Reviewer Instructions"),
            "Should include Security Reviewer instructions"
        );
        assert!(
            prompt.contains("Review code for security vulnerabilities"),
            "Should include Security Reviewer content"
        );
        assert!(
            prompt.contains("### Architecture Reviewer Instructions"),
            "Should include Architecture Reviewer instructions"
        );
        assert!(
            prompt.contains("Review system design and architecture"),
            "Should include Architecture Reviewer content"
        );

        // Should NOT contain inactive hat's instructions
        assert!(
            !prompt.contains("### Correctness Reviewer Instructions"),
            "Should NOT include Correctness Reviewer instructions"
        );
    }

    #[test]
    fn test_no_active_hats_no_instructions() {
        // No active hats = no instructions section (but topology table still present)
        let yaml = r#"
hats:
  security_reviewer:
    name: "Security Reviewer"
    triggers: ["review.security"]
    instructions: "Review code for security vulnerabilities."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // No active hats
        let active_hats: Vec<&ralph_proto::Hat> = vec![];

        let prompt = ralph.build_prompt("Events", &active_hats);

        // Should NOT contain any instructions
        assert!(
            !prompt.contains("### Security Reviewer Instructions"),
            "Should NOT include instructions when no active hats"
        );
        assert!(
            !prompt.contains("Review code for security vulnerabilities"),
            "Should NOT include instructions content when no active hats"
        );

        // But topology table should still be present
        assert!(prompt.contains("## HATS"), "Should still have HATS section");
        assert!(
            prompt.contains("| Hat | Triggers On | Publishes |"),
            "Should still have topology table"
        );
    }

    #[test]
    fn test_topology_table_only_when_ralph_coordinating() {
        // Topology table + Mermaid shown only when Ralph is coordinating (no active hats)
        // When a hat is active, skip the table to reduce token usage
        let yaml = r#"
hats:
  security_reviewer:
    name: "Security Reviewer"
    triggers: ["review.security"]
    instructions: "Security instructions."
  architecture_reviewer:
    name: "Architecture Reviewer"
    triggers: ["review.architecture"]
    instructions: "Architecture instructions."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // Test 1: No active hats (Ralph coordinating) - should show table + Mermaid
        let prompt_coordinating = ralph.build_prompt("Events", &[]);

        assert!(
            prompt_coordinating.contains("## HATS"),
            "Should have HATS section when coordinating"
        );
        assert!(
            prompt_coordinating.contains("| Hat | Triggers On | Publishes |"),
            "Should have topology table when coordinating"
        );
        assert!(
            prompt_coordinating.contains("```mermaid"),
            "Should have Mermaid diagram when coordinating"
        );

        // Test 2: Active hat - should NOT show table/Mermaid, just instructions
        let security_hat = registry
            .get(&ralph_proto::HatId::new("security_reviewer"))
            .unwrap();
        let prompt_active = ralph.build_prompt("Events", &[security_hat]);

        assert!(
            prompt_active.contains("## ACTIVE HAT"),
            "Should have ACTIVE HAT section when hat is active"
        );
        assert!(
            !prompt_active.contains("| Hat | Triggers On | Publishes |"),
            "Should NOT have topology table when hat is active"
        );
        assert!(
            !prompt_active.contains("```mermaid"),
            "Should NOT have Mermaid diagram when hat is active"
        );
        assert!(
            prompt_active.contains("### Security Reviewer Instructions"),
            "Should still have the active hat's instructions"
        );
    }

    // === Memories/Scratchpad Exclusivity Tests ===

    #[test]
    fn test_scratchpad_always_included() {
        // Scratchpad section should always be included (regardless of memories mode)
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            prompt.contains("### 0b. SCRATCHPAD"),
            "Scratchpad section should be included"
        );
        assert!(
            prompt.contains("`.ralph/agent/scratchpad.md`"),
            "Scratchpad path should be referenced"
        );
        assert!(
            prompt.contains("auto-injected"),
            "Auto-injection should be documented"
        );
    }

    #[test]
    fn test_scratchpad_included_with_memories_enabled() {
        // When memories are enabled, scratchpad should STILL be included (not excluded)
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None)
            .with_memories_enabled(true);

        let prompt = ralph.build_prompt("", &[]);

        // Scratchpad should still be present
        assert!(
            prompt.contains("### 0b. SCRATCHPAD"),
            "Scratchpad section should be included even with memories enabled"
        );
        assert!(
            prompt.contains("**Always append**"),
            "Append instruction should be documented"
        );

        // Tasks section is now injected via the skills pipeline (not in core_prompt)
        assert!(
            !prompt.contains("### 0c. TASKS"),
            "Tasks section should NOT be in core_prompt — injected via skills pipeline"
        );
    }

    #[test]
    fn test_no_tasks_section_in_core_prompt() {
        // Tasks section is now in the skills pipeline, not core_prompt
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        // core_prompt no longer contains the tasks section (injected via skills)
        assert!(
            !prompt.contains("### 0c. TASKS"),
            "Tasks section should NOT be in core_prompt — injected via skills pipeline"
        );
    }

    #[test]
    fn test_workflow_references_both_scratchpad_and_tasks_with_memories() {
        // When memories enabled, workflow should reference BOTH scratchpad AND tasks CLI
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None)
            .with_memories_enabled(true);

        let prompt = ralph.build_prompt("", &[]);

        // Workflow should mention scratchpad
        assert!(
            prompt.contains("update scratchpad"),
            "Workflow should reference scratchpad when memories enabled"
        );
        // Workflow should also mention tasks CLI
        assert!(
            prompt.contains("ralph tools task"),
            "Workflow should reference tasks CLI when memories enabled"
        );
    }

    #[test]
    fn test_multi_hat_mode_workflow_with_memories_enabled() {
        // Multi-hat mode should reference scratchpad AND tasks CLI when memories enabled
        let yaml = r#"
hats:
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None)
            .with_memories_enabled(true);

        let prompt = ralph.build_prompt("", &[]);

        // Multi-hat workflow should mention scratchpad
        assert!(
            prompt.contains("scratchpad"),
            "Multi-hat workflow should reference scratchpad when memories enabled"
        );
        // And tasks CLI
        assert!(
            prompt.contains("ralph tools task add"),
            "Multi-hat workflow should reference tasks CLI when memories enabled"
        );
    }

    #[test]
    fn test_guardrails_adapt_to_memories_mode() {
        // When memories enabled, guardrails should encourage saving to memories
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None)
            .with_memories_enabled(true);

        let prompt = ralph.build_prompt("", &[]);

        // With memories enabled + include_scratchpad still true (default),
        // the guardrail transformation doesn't apply
        // Just verify the prompt generates correctly
        assert!(
            prompt.contains("### GUARDRAILS"),
            "Guardrails section should be present"
        );
    }

    #[test]
    fn test_guardrails_present_without_memories() {
        // Without memories, guardrails should still be present
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        // memories_enabled defaults to false

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            prompt.contains("### GUARDRAILS"),
            "Guardrails section should be present"
        );
    }

    // === Task Completion Verification Tests ===

    #[test]
    fn test_task_closure_verification_in_done_section() {
        // When memories/tasks mode is enabled, the DONE section should include
        // task verification requirements
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None)
            .with_memories_enabled(true);

        let prompt = ralph.build_prompt("", &[]);

        // The tasks CLI instructions are now injected via the skills pipeline,
        // but the DONE section still requires task verification before completion
        assert!(
            prompt.contains("ralph tools task ready"),
            "Should reference task ready command in DONE section"
        );
        assert!(
            prompt.contains("MUST NOT emit the completion event while tasks remain open"),
            "Should require tasks closed before completion"
        );
    }

    #[test]
    fn test_workflow_verify_and_commit_step() {
        // Solo mode with memories should have VERIFY & COMMIT step
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None)
            .with_memories_enabled(true);

        let prompt = ralph.build_prompt("", &[]);

        // Should have VERIFY & COMMIT step
        assert!(
            prompt.contains("### 4. VERIFY & COMMIT"),
            "Should have VERIFY & COMMIT step in workflow"
        );
        assert!(
            prompt.contains("run tests and verify"),
            "Should require verification"
        );
        assert!(
            prompt.contains("ralph tools task close"),
            "Should reference task close command"
        );
    }

    #[test]
    fn test_scratchpad_mode_still_has_commit_step() {
        // Scratchpad-only mode (no memories) should have COMMIT step
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        // memories_enabled defaults to false

        let prompt = ralph.build_prompt("", &[]);

        // Scratchpad mode uses different format - COMMIT step without task CLI
        assert!(
            prompt.contains("### 4. COMMIT"),
            "Should have COMMIT step in workflow"
        );
        assert!(
            prompt.contains("mark the task `[x]`"),
            "Should mark task in scratchpad"
        );
        // Scratchpad mode doesn't have the TASKS section
        assert!(
            !prompt.contains("### 0c. TASKS"),
            "Scratchpad mode should not have TASKS section"
        );
    }

    // === Objective Section Tests ===

    #[test]
    fn test_objective_section_present_with_set_objective() {
        // When objective is set via set_objective(), OBJECTIVE section should appear
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Implement user authentication with JWT tokens".to_string());

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            prompt.contains("## OBJECTIVE"),
            "Should have OBJECTIVE section when objective is set"
        );
        assert!(
            prompt.contains("Implement user authentication with JWT tokens"),
            "OBJECTIVE should contain the original user prompt"
        );
        assert!(
            prompt.contains("This is your primary goal"),
            "OBJECTIVE should emphasize this is the primary goal"
        );
    }

    #[test]
    fn test_objective_reinforced_in_done_section() {
        // The objective should be restated in the DONE section (bookend pattern)
        // when Ralph is coordinating (no active hats)
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Fix the login bug in auth module".to_string());

        let prompt = ralph.build_prompt("", &[]);

        // Check DONE section contains objective reinforcement
        let done_pos = prompt.find("## DONE").expect("Should have DONE section");
        let after_done = &prompt[done_pos..];

        assert!(
            after_done.contains("Remember your objective"),
            "DONE section should remind about objective"
        );
        assert!(
            after_done.contains("Fix the login bug in auth module"),
            "DONE section should restate the objective"
        );
    }

    #[test]
    fn test_objective_appears_before_pending_events() {
        // OBJECTIVE should appear BEFORE PENDING EVENTS for prominence
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Build feature X".to_string());

        let context = "Event: task.start - Build feature X";
        let prompt = ralph.build_prompt(context, &[]);

        let objective_pos = prompt.find("## OBJECTIVE").expect("Should have OBJECTIVE");
        let events_pos = prompt
            .find("## PENDING EVENTS")
            .expect("Should have PENDING EVENTS");

        assert!(
            objective_pos < events_pos,
            "OBJECTIVE ({}) should appear before PENDING EVENTS ({})",
            objective_pos,
            events_pos
        );
    }

    #[test]
    fn test_no_objective_when_not_set() {
        // When no objective has been set, no OBJECTIVE section should appear
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let context = "Event: build.done - Build completed successfully";
        let prompt = ralph.build_prompt(context, &[]);

        assert!(
            !prompt.contains("## OBJECTIVE"),
            "Should NOT have OBJECTIVE section when objective not set"
        );
    }

    #[test]
    fn test_objective_set_correctly() {
        // Test that set_objective stores the objective and it appears in prompt
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Review this PR for security issues".to_string());

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            prompt.contains("Review this PR for security issues"),
            "Should show the stored objective"
        );
    }

    #[test]
    fn test_objective_with_events_context() {
        // Objective should appear even when context has other events (not task.start)
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Implement feature Y".to_string());

        let context =
            "Event: build.done - Previous build succeeded\nEvent: test.passed - All tests green";
        let prompt = ralph.build_prompt(context, &[]);

        assert!(
            prompt.contains("## OBJECTIVE"),
            "Should have OBJECTIVE section"
        );
        assert!(
            prompt.contains("Implement feature Y"),
            "OBJECTIVE should contain the stored objective"
        );
    }

    #[test]
    fn test_done_section_without_objective() {
        // When no objective, DONE section should still work but without reinforcement
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("", &[]);

        assert!(prompt.contains("## DONE"), "Should have DONE section");
        assert!(
            prompt.contains("LOOP_COMPLETE"),
            "DONE should mention completion event"
        );
        assert!(
            !prompt.contains("Remember your objective"),
            "Should NOT have objective reinforcement without objective"
        );
    }

    #[test]
    fn test_objective_persists_across_iterations() {
        // Objective is present in prompt even when context has no task.start event
        // (simulating iteration 2+ where the start event has been consumed)
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Build a REST API with authentication".to_string());

        // Simulate iteration 2: only non-start events present
        let context = "Event: build.done - Build completed";
        let prompt = ralph.build_prompt(context, &[]);

        assert!(
            prompt.contains("## OBJECTIVE"),
            "OBJECTIVE should persist even without task.start in context"
        );
        assert!(
            prompt.contains("Build a REST API with authentication"),
            "Stored objective should appear in later iterations"
        );
    }

    #[test]
    fn test_done_section_suppressed_when_hat_active() {
        // When active_hats is non-empty, prompt does NOT contain ## DONE
        let yaml = r#"
hats:
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done"]
    instructions: "Build the code."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Implement feature X".to_string());

        let builder = registry.get(&ralph_proto::HatId::new("builder")).unwrap();
        let prompt = ralph.build_prompt("Event: build.task - Do the build", &[builder]);

        assert!(
            !prompt.contains("## DONE"),
            "DONE section should be suppressed when a hat is active"
        );
        assert!(
            !prompt.contains("LOOP_COMPLETE"),
            "Completion promise should NOT appear when a hat is active"
        );
        // But objective should still be visible
        assert!(
            prompt.contains("## OBJECTIVE"),
            "OBJECTIVE should still appear even when hat is active"
        );
        assert!(
            prompt.contains("Implement feature X"),
            "Objective content should be visible to active hat"
        );
    }

    #[test]
    fn test_done_section_present_when_coordinating() {
        // When active_hats is empty, prompt contains ## DONE with objective reinforcement
        let yaml = r#"
hats:
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Complete the TDD cycle".to_string());

        // No active hats - Ralph is coordinating
        let prompt = ralph.build_prompt("Event: build.done - Build finished", &[]);

        assert!(
            prompt.contains("## DONE"),
            "DONE section should appear when Ralph is coordinating"
        );
        assert!(
            prompt.contains("LOOP_COMPLETE"),
            "Completion promise should appear when coordinating"
        );
    }

    #[test]
    fn test_objective_in_done_section_when_coordinating() {
        // DONE section includes "Remember your objective" when Ralph is coordinating
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Deploy the application".to_string());

        let prompt = ralph.build_prompt("", &[]);

        let done_pos = prompt.find("## DONE").expect("Should have DONE section");
        let after_done = &prompt[done_pos..];

        assert!(
            after_done.contains("Remember your objective"),
            "DONE section should remind about objective when coordinating"
        );
        assert!(
            after_done.contains("Deploy the application"),
            "DONE section should contain the objective text"
        );
    }

    // === Event Publishing Guide Tests ===

    #[test]
    fn test_event_publishing_guide_with_receivers() {
        // When a hat publishes events and other hats receive them,
        // the guide should show who receives each event
        let yaml = r#"
hats:
  builder:
    name: "Builder"
    description: "Builds and tests code"
    triggers: ["build.task"]
    publishes: ["build.done", "build.blocked"]
  confessor:
    name: "Confessor"
    description: "Produces a ConfessionReport; rewarded for honesty"
    triggers: ["build.done"]
    publishes: ["confession.done"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // Get the builder hat as active
        let builder = registry.get(&ralph_proto::HatId::new("builder")).unwrap();
        let prompt = ralph.build_prompt("[build.task] Build the feature", &[builder]);

        // Should include Event Publishing Guide
        assert!(
            prompt.contains("### Event Publishing Guide"),
            "Should include Event Publishing Guide section"
        );
        assert!(
            prompt.contains("When you publish:"),
            "Guide should explain what happens when publishing"
        );
        // build.done has a receiver (Confessor)
        assert!(
            prompt.contains("`build.done` → Received by: Confessor"),
            "Should show Confessor receives build.done"
        );
        assert!(
            prompt.contains("Produces a ConfessionReport; rewarded for honesty"),
            "Should include receiver's description"
        );
        // build.blocked has no receiver, so falls back to Ralph
        assert!(
            prompt.contains("`build.blocked` → Received by: Ralph (coordinates next steps)"),
            "Should show Ralph receives orphan events"
        );
    }

    #[test]
    fn test_event_publishing_guide_no_publishes() {
        // When a hat doesn't publish any events, no guide should appear
        let yaml = r#"
hats:
  observer:
    name: "Observer"
    description: "Only observes"
    triggers: ["events.*"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let observer = registry.get(&ralph_proto::HatId::new("observer")).unwrap();
        let prompt = ralph.build_prompt("[events.start] Start", &[observer]);

        // Should NOT include Event Publishing Guide
        assert!(
            !prompt.contains("### Event Publishing Guide"),
            "Should NOT include Event Publishing Guide when hat has no publishes"
        );
    }

    #[test]
    fn test_event_publishing_guide_all_orphan_events() {
        // When all published events have no receivers, all should show Ralph
        let yaml = r#"
hats:
  solo:
    name: "Solo"
    triggers: ["solo.start"]
    publishes: ["solo.done", "solo.failed"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let solo = registry.get(&ralph_proto::HatId::new("solo")).unwrap();
        let prompt = ralph.build_prompt("[solo.start] Go", &[solo]);

        assert!(
            prompt.contains("### Event Publishing Guide"),
            "Should include guide even for orphan events"
        );
        assert!(
            prompt.contains("`solo.done` → Received by: Ralph (coordinates next steps)"),
            "Orphan solo.done should go to Ralph"
        );
        assert!(
            prompt.contains("`solo.failed` → Received by: Ralph (coordinates next steps)"),
            "Orphan solo.failed should go to Ralph"
        );
    }

    #[test]
    fn test_event_publishing_guide_multiple_receivers() {
        // When an event has multiple receivers, all should be listed
        let yaml = r#"
hats:
  broadcaster:
    name: "Broadcaster"
    triggers: ["broadcast.start"]
    publishes: ["signal.sent"]
  listener1:
    name: "Listener1"
    description: "First listener"
    triggers: ["signal.sent"]
  listener2:
    name: "Listener2"
    description: "Second listener"
    triggers: ["signal.sent"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let broadcaster = registry
            .get(&ralph_proto::HatId::new("broadcaster"))
            .unwrap();
        let prompt = ralph.build_prompt("[broadcast.start] Go", &[broadcaster]);

        assert!(
            prompt.contains("### Event Publishing Guide"),
            "Should include guide"
        );
        // Both listeners should be mentioned (order may vary due to HashMap iteration)
        assert!(
            prompt.contains("Listener1 (First listener)"),
            "Should list Listener1 as receiver"
        );
        assert!(
            prompt.contains("Listener2 (Second listener)"),
            "Should list Listener2 as receiver"
        );
    }

    #[test]
    fn test_event_publishing_guide_excludes_self() {
        // If a hat subscribes to its own event, it should NOT be listed as receiver
        let yaml = r#"
hats:
  looper:
    name: "Looper"
    triggers: ["loop.continue", "loop.start"]
    publishes: ["loop.continue"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let looper = registry.get(&ralph_proto::HatId::new("looper")).unwrap();
        let prompt = ralph.build_prompt("[loop.start] Start", &[looper]);

        assert!(
            prompt.contains("### Event Publishing Guide"),
            "Should include guide"
        );
        // Self-reference should be excluded, so should fall back to Ralph
        assert!(
            prompt.contains("`loop.continue` → Received by: Ralph (coordinates next steps)"),
            "Self-subscription should be excluded, falling back to Ralph"
        );
    }

    #[test]
    fn test_event_publishing_guide_receiver_without_description() {
        // When a receiver has no description, just show the name
        let yaml = r#"
hats:
  sender:
    name: "Sender"
    triggers: ["send.start"]
    publishes: ["message.sent"]
  receiver:
    name: "NoDescReceiver"
    triggers: ["message.sent"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let sender = registry.get(&ralph_proto::HatId::new("sender")).unwrap();
        let prompt = ralph.build_prompt("[send.start] Go", &[sender]);

        assert!(
            prompt.contains("`message.sent` → Received by: NoDescReceiver"),
            "Should show receiver name without parentheses when no description"
        );
        // Should NOT have empty parentheses
        assert!(
            !prompt.contains("NoDescReceiver ()"),
            "Should NOT have empty parentheses for receiver without description"
        );
    }

    // === Event Publishing Constraint Tests ===

    #[test]
    fn test_constraint_lists_valid_events_when_coordinating() {
        // When Ralph is coordinating (no active hats), the prompt should include
        // a CONSTRAINT listing valid events to publish
        let yaml = r#"
hats:
  test_writer:
    name: "Test Writer"
    triggers: ["tdd.start"]
    publishes: ["test.written"]
  implementer:
    name: "Implementer"
    triggers: ["test.written"]
    publishes: ["test.passing"]
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // No active hats - Ralph is coordinating
        let prompt = ralph.build_prompt("[task.start] Do TDD for feature X", &[]);

        // Should contain CONSTRAINT with valid events
        assert!(
            prompt.contains("**CONSTRAINT:**"),
            "Prompt should include CONSTRAINT when coordinating"
        );
        assert!(
            prompt.contains("tdd.start"),
            "CONSTRAINT should list tdd.start as valid event"
        );
        assert!(
            prompt.contains("test.written"),
            "CONSTRAINT should list test.written as valid event"
        );
        assert!(
            prompt.contains("Publishing other events will have no effect"),
            "CONSTRAINT should warn about invalid events"
        );
    }

    #[test]
    fn test_no_constraint_when_hat_is_active() {
        // When a hat is active, the CONSTRAINT should NOT appear
        // (the active hat has its own Event Publishing Guide)
        let yaml = r#"
hats:
  builder:
    name: "Builder"
    triggers: ["build.task"]
    publishes: ["build.done"]
    instructions: "Build the code."
"#;
        let config: RalphConfig = serde_yaml::from_str(yaml).unwrap();
        let registry = HatRegistry::from_config(&config);
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        // Builder hat is active
        let builder = registry.get(&ralph_proto::HatId::new("builder")).unwrap();
        let prompt = ralph.build_prompt("[build.task] Build feature X", &[builder]);

        // Should NOT contain the coordinating CONSTRAINT
        assert!(
            !prompt.contains("**CONSTRAINT:** You MUST only publish events from this list"),
            "Active hat should NOT have coordinating CONSTRAINT"
        );

        // Should have Event Publishing Guide instead
        assert!(
            prompt.contains("### Event Publishing Guide"),
            "Active hat should have Event Publishing Guide"
        );
    }

    #[test]
    fn test_no_constraint_when_no_hats() {
        // When there are no hats (solo mode), no CONSTRAINT should appear
        let config = RalphConfig::default();
        let registry = HatRegistry::new(); // Empty registry
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("[task.start] Do something", &[]);

        // Should NOT contain CONSTRAINT (no hats to coordinate)
        assert!(
            !prompt.contains("**CONSTRAINT:**"),
            "Solo mode should NOT have CONSTRAINT"
        );
    }

    // === Human Guidance Injection Tests ===

    #[test]
    fn test_single_guidance_injection() {
        // Single human.guidance message should be injected as-is (no numbered list)
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_robot_guidance(vec!["Focus on error handling first".to_string()]);

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            prompt.contains("## ROBOT GUIDANCE"),
            "Should include ROBOT GUIDANCE section"
        );
        assert!(
            prompt.contains("Focus on error handling first"),
            "Should contain the guidance message"
        );
        // Single message should NOT be numbered
        assert!(
            !prompt.contains("1. Focus on error handling first"),
            "Single guidance should not be numbered"
        );
    }

    #[test]
    fn test_multiple_guidance_squashing() {
        // Multiple human.guidance messages should be squashed into a numbered list
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_robot_guidance(vec![
            "Focus on error handling".to_string(),
            "Use the existing retry pattern".to_string(),
            "Check edge cases for empty input".to_string(),
        ]);

        let prompt = ralph.build_prompt("", &[]);

        assert!(
            prompt.contains("## ROBOT GUIDANCE"),
            "Should include ROBOT GUIDANCE section"
        );
        assert!(
            prompt.contains("1. Focus on error handling"),
            "First guidance should be numbered 1"
        );
        assert!(
            prompt.contains("2. Use the existing retry pattern"),
            "Second guidance should be numbered 2"
        );
        assert!(
            prompt.contains("3. Check edge cases for empty input"),
            "Third guidance should be numbered 3"
        );
    }

    #[test]
    fn test_guidance_appears_in_prompt_before_events() {
        // ROBOT GUIDANCE should appear after OBJECTIVE but before PENDING EVENTS
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_objective("Build feature X".to_string());
        ralph.set_robot_guidance(vec!["Use the new API".to_string()]);

        let prompt = ralph.build_prompt("Event: build.task - Do the work", &[]);

        let objective_pos = prompt.find("## OBJECTIVE").expect("Should have OBJECTIVE");
        let guidance_pos = prompt
            .find("## ROBOT GUIDANCE")
            .expect("Should have ROBOT GUIDANCE");
        let events_pos = prompt
            .find("## PENDING EVENTS")
            .expect("Should have PENDING EVENTS");

        assert!(
            objective_pos < guidance_pos,
            "OBJECTIVE ({}) should come before ROBOT GUIDANCE ({})",
            objective_pos,
            guidance_pos
        );
        assert!(
            guidance_pos < events_pos,
            "ROBOT GUIDANCE ({}) should come before PENDING EVENTS ({})",
            guidance_pos,
            events_pos
        );
    }

    #[test]
    fn test_guidance_cleared_after_injection() {
        // After build_prompt consumes guidance, clear_robot_guidance should leave it empty
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let mut ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);
        ralph.set_robot_guidance(vec!["First guidance".to_string()]);

        // First prompt should include guidance
        let prompt1 = ralph.build_prompt("", &[]);
        assert!(
            prompt1.contains("## ROBOT GUIDANCE"),
            "First prompt should have guidance"
        );

        // Clear guidance (as EventLoop would)
        ralph.clear_robot_guidance();

        // Second prompt should NOT include guidance
        let prompt2 = ralph.build_prompt("", &[]);
        assert!(
            !prompt2.contains("## ROBOT GUIDANCE"),
            "After clearing, prompt should not have guidance"
        );
    }

    #[test]
    fn test_no_injection_when_no_guidance() {
        // When no guidance events, prompt should not have ROBOT GUIDANCE section
        let config = RalphConfig::default();
        let registry = HatRegistry::new();
        let ralph = HatlessRalph::new("LOOP_COMPLETE", config.core.clone(), &registry, None);

        let prompt = ralph.build_prompt("Event: build.task - Do the work", &[]);

        assert!(
            !prompt.contains("## ROBOT GUIDANCE"),
            "Should NOT include ROBOT GUIDANCE when no guidance set"
        );
    }
}