use rmcp::model::{
GetPromptRequestParams, GetPromptResult, Prompt, PromptArgument, PromptMessage, Role,
};
fn required_arg(name: &str, desc: &str) -> PromptArgument {
PromptArgument::new(name)
.with_description(desc)
.with_required(true)
}
fn assistant_text(text: &str) -> PromptMessage {
PromptMessage::new_text(
Role::Assistant,
crate::server::policy_guard::redact_model_text(text),
)
}
pub fn list_prompts() -> Vec<Prompt> {
vec![
Prompt::new(
"context-focus",
Some("Set task intent and optimize context for a specific task"),
Some(vec![required_arg("task", "What you are working on")]),
),
Prompt::new(
"context-review",
Some("Review current context state: items, pressure, budget, recommendations"),
None,
),
Prompt::new(
"context-reset",
Some("Clear all overlays and reset context state"),
None,
),
Prompt::new(
"context-pin",
Some("Pin a file to keep it in full context"),
Some(vec![required_arg("path", "Path to the file to pin")]),
),
Prompt::new(
"context-budget",
Some("Set the token budget for this session"),
Some(vec![required_arg(
"tokens",
"Max tokens for the context window",
)]),
),
]
}
pub fn get_prompt(
params: &GetPromptRequestParams,
ledger: &lean_ctx::core::context_ledger::ContextLedger,
) -> Option<GetPromptResult> {
match params.name.as_str() {
"context-focus" => {
let task = params
.arguments
.as_ref()
.and_then(|a| a.get("task"))
.and_then(|v| v.as_str())
.unwrap_or("general development");
Some(get_context_focus(task, ledger))
}
"context-review" => Some(get_context_review(ledger)),
"context-reset" => Some(get_context_reset()),
"context-pin" => {
let path = params
.arguments
.as_ref()
.and_then(|a| a.get("path"))
.and_then(|v| v.as_str())
.unwrap_or("");
Some(get_context_pin(path))
}
"context-budget" => {
let tokens = params
.arguments
.as_ref()
.and_then(|a| a.get("tokens"))
.and_then(|v| v.as_str())
.unwrap_or("128000");
Some(get_context_budget(tokens))
}
_ => None,
}
}
fn get_context_focus(
task: &str,
ledger: &lean_ctx::core::context_ledger::ContextLedger,
) -> GetPromptResult {
let pressure = ledger.pressure();
let msg = format!(
"Focus context on task: {task}\n\
Current state: {} files, {:.0}% pressure\n\
Use ctx_compose(task=\"{task}\") to select the files and symbols this task needs.\n\
Read those as 'full'; exclude or evict the rest with ctx_control.",
ledger.entries.len(),
pressure.utilization * 100.0,
);
GetPromptResult::new(vec![assistant_text(&msg)])
}
fn get_context_review(ledger: &lean_ctx::core::context_ledger::ContextLedger) -> GetPromptResult {
let summary = ledger.format_summary();
let adjusted = ledger.adjusted_total_saved();
let bounce_info = match lean_ctx::core::bounce_tracker::global().lock() {
Ok(bt) => bt.format_summary(),
_ => String::new(),
};
let msg = format!(
"Context Review:\n{summary}\nAdjusted savings: {adjusted} tokens\n{bounce_info}\n\n\
Use ctx_metrics() for a detailed breakdown or ctx_control(action=\"list\") to review pins and exclusions.",
);
GetPromptResult::new(vec![assistant_text(&msg)])
}
fn get_context_reset() -> GetPromptResult {
GetPromptResult::new(vec![assistant_text(
"Reset context: Use ctx_control(action=\"reset\") to clear all overlays and reset ledger states.",
)])
}
fn get_context_pin(path: &str) -> GetPromptResult {
let msg = format!(
"Pin file: Use ctx_control(action=\"pin\", target=\"{path}\") to keep this file in full context regardless of pressure."
);
GetPromptResult::new(vec![assistant_text(&msg)])
}
fn get_context_budget(tokens: &str) -> GetPromptResult {
let msg = format!(
"Set budget: Configure the context window to {tokens} tokens. \
Use ctx_session(action=\"budget\", value=\"{tokens}\") or set LCTX_CONTEXT_BUDGET={tokens} in your environment."
);
GetPromptResult::new(vec![assistant_text(&msg)])
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn list_returns_five_prompts() {
let prompts = list_prompts();
assert_eq!(prompts.len(), 5);
}
#[test]
fn context_focus_has_task_arg() {
let prompts = list_prompts();
let focus = prompts.iter().find(|p| p.name == "context-focus").unwrap();
let args = focus.arguments.as_ref().unwrap();
assert_eq!(args[0].name, "task");
}
#[test]
fn get_unknown_prompt_returns_none() {
let ledger = lean_ctx::core::context_ledger::ContextLedger::new();
let params = GetPromptRequestParams::new("unknown-prompt");
assert!(get_prompt(¶ms, &ledger).is_none());
}
#[test]
fn get_context_review_returns_result() {
let ledger = lean_ctx::core::context_ledger::ContextLedger::new();
let params = GetPromptRequestParams::new("context-review");
let result = get_prompt(¶ms, &ledger);
assert!(result.is_some());
}
}