| name | lc-context |
| description | Use whenever working in a project that has a `.linear_canal_data/` folder — this signals Linear Canal has indexed the codebase. Invoke before any Glob, Grep, or raw file reads. Covers: "how does X work", "where is Y defined", "what files handle Z", explaining architecture, fixing bugs, adding features, or any file edit. The ctx files contain pre-compiled insights — reading them first saves 80-95% of tokens vs raw source exploration. If you see `.linear_canal_data/` in the project root, use this skill first.
|
Linear Canal — lc-context
Linear Canal has indexed this codebase into pre-compiled .ctx files. Reading
them costs 200–800 tokens each instead of the thousands you'd spend walking raw
source files.
Step 0 — Find the project ID
The project ID is the directory name inside .linear_canal_data/. Find it with:
Bash: ls .linear_canal_data/
All ctx files live at:
.linear_canal_data/<project_id>/ctx/
The ctx files
Read these in order — stop when you have enough context.
1. ARCHITECTURE.ctx — always read first
Full module map, entry points, tech stack, file counts per module, deployment
notes. Answers most "where does X live" questions without opening a single source
file.
Read: .linear_canal_data/<project_id>/ctx/ARCHITECTURE.ctx
2. INTERFACES.ctx — find any exported symbol
Every exported function, class, and method across the codebase, grouped by
module. Use when you know the symbol name but not the file.
Read: .linear_canal_data/<project_id>/ctx/INTERFACES.ctx
3. RISKS.ctx — before editing anything
Files flagged for LONG_FUNCTION, SILENT_ERROR, NO_TEST_COVERAGE, STALE_TODO —
with exact paths and line numbers. Read this before touching a file so you know
what to watch out for.
Read: .linear_canal_data/<project_id>/ctx/RISKS.ctx
4. DEPENDENCIES.ctx — before adding imports
Module dependency graph and breaking-change edges. Read before adding a new
import or creating a cross-module dependency.
5. PATTERNS.ctx — before writing new code
Detected design patterns (FACTORY, SINGLETON, MIDDLEWARE, etc.) with the files
where they're used. Helps you match the project's conventions.
6. <module>.ctx — deep dive into one module
When ARCHITECTURE.ctx tells you which module to look at, read that module's own
ctx file for detailed context: purpose, public interface, risks, full file list.
Read: .linear_canal_data/<project_id>/ctx/<module_name>.ctx
Recommended workflow
1. Bash: ls .linear_canal_data/ → get project ID
2. Read ARCHITECTURE.ctx → orient (~400 tokens)
3. Identify relevant module(s)
4. Read <module>.ctx → deep context (~300 tokens)
5. Read INTERFACES.ctx if you need a symbol → (~500 tokens)
6. Read RISKS.ctx for any file you'll edit
7. Only then open raw source files — and only the specific ones needed
Total: ~1,500 tokens for full project understanding vs 10,000–50,000 for raw exploration.
MCP tools
If the Linear Canal MCP server is running (auto-started via .mcp.json when
the plugin is installed, or manually via linear-canal serve), you have three
additional tools:
lc_search — semantic search
Searches Qdrant vector collections for natural-language queries.
lc_search("user authentication JWT token validation", limit=5, tier="HIGH")
Use when you need the exact location of a concept and ARCHITECTURE.ctx gave you
the module but not the line.
lc_impact — change impact before editing
lc_impact(file_path="src/services/auth.py")
Returns: dependents, coupling score, related modules, test coverage. Call this
before editing any file that might have downstream effects.
lc_context — task-specific context bundle
lc_context(
task_description="add rate limiting to the API authentication endpoint",
token_budget=8000
)
Returns the most relevant ctx + code chunks for a specific task, pre-filtered
to your token budget. Best entry point for complex multi-file tasks.
If MCP tools aren't available (server not running), fall back to the ctx
file workflow above — it covers ~90% of the same ground.
Token economics
| Approach | Tokens | Signal |
|---|
| Glob + read all source files | 20k–100k | High noise |
| ARCHITECTURE + module ctx | 600–1,500 | Focused |
lc_context() for a task | 2k–8k | Targeted |
lc_search() for a symbol | 200–500 | Precise |
File reference
.linear_canal_data/<project_id>/
ctx/
ARCHITECTURE.ctx ← start here always
INTERFACES.ctx ← find any export
RISKS.ctx ← before editing
DEPENDENCIES.ctx ← before importing
PATTERNS.ctx ← before adding code
OWNERSHIP.ctx ← coupling / owners
<module>.ctx ← per-module deep dive
scores.json ← per-file importance scores
graph.db ← SQLite graph store
.LC/
CLAUDE.md ← agent instructions (Claude Code / Kilo / Roo)
AGENTS.md ← agent instructions (OpenCode / universal)
GEMINI.md ← agent instructions (Gemini CLI)
.cursorrules ← agent instructions (Cursor)
