lean-ctx 3.9.1

Context Runtime for AI Agents with CCP. 71 MCP tools, 10 read modes, 95+ compression patterns, cross-session memory (CCP), persistent AI knowledge with temporal facts + contradiction detection, multi-agent context sharing, LITM-aware positioning, AAAK compact format, adaptive compression with Thompson Sampling bandits. Supports 24+ AI tools. Reduces LLM token consumption by up to 99%.
Documentation 
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//! The rules/skill payloads lean-ctx injects: shared + dedicated markdown,
//! Cursor MDC frontmatter, and per-agent rule paths.
//!
//! Rule CONTENT is delegated to `core::rules_canonical` — this module only
//! handles format dispatch and the Cursor-specific frontmatter.

use std::path::{Path, PathBuf};

use super::RulesFormat;
use crate::core::config::CompressionLevel;
use crate::core::rules_canonical::{self as rc, Wrapper};

/// The wrapper a Cursor mdc at `mdc_path` should carry (GL #1153): the
/// honest `HookCovered` profile when the sibling `hooks.json` (always under
/// the same `.cursor/` dir) shows lean-ctx compressing the native tools,
/// otherwise the full `Dedicated` mapping. Path-derived so isolated test
/// homes and the real `~/.cursor` behave identically.
pub(super) fn cursor_wrapper_for_mdc(mdc_path: &Path) -> Wrapper {
    let covered = mdc_path
        .parent()
        .and_then(Path::parent)
        .is_some_and(|cursor_dir| {
            crate::core::rules_channel::cursor_hooks_json_covers(&cursor_dir.join("hooks.json"))
        });
    if covered {
        Wrapper::HookCovered
    } else {
        Wrapper::Dedicated
    }
}

/// Wrap a rendered rules body in the Cursor mdc frontmatter. The description
/// stays profile-neutral: whether native tools are replaced (Dedicated) or
/// hook-covered (GL #1153) is stated by the body itself.
pub(crate) fn cursor_mdc_document(body: &str) -> String {
    format!(
        "---\n\
         description: \"lean-ctx: context compression layer — \
         tool guidance in rule body.\"\n\
         globs: **/*\n\
         alwaysApply: true\n\
         ---\n\n\
         {body}"
    )
}

pub(super) fn rules_content(
    format: &RulesFormat,
    level: CompressionLevel,
    wrapper: Wrapper,
) -> String {
    let shadow = crate::core::config::Config::load().shadow_mode;
    match format {
        RulesFormat::SharedMarkdown => rc::render(shadow, Wrapper::Shared, level),
        RulesFormat::DedicatedMarkdown => rc::render(shadow, Wrapper::Dedicated, level),
        RulesFormat::CursorMdc => cursor_mdc_document(&rc::render(shadow, wrapper, level)),
    }
}

pub fn opencode_dedicated_rules_path(home: &std::path::Path) -> PathBuf {
    home.join(".config/opencode/rules/lean-ctx.md")
}

pub fn gemini_dedicated_rules_path(home: &std::path::Path) -> PathBuf {
    home.join(".gemini").join(GEMINI_DEDICATED_CONTEXT_FILENAME)
}

/// The `context.fileName` entry registered for Gemini in dedicated mode.
pub const GEMINI_DEDICATED_CONTEXT_FILENAME: &str = "LEANCTX.md";