Carrick

Carrick

TypeScript codebase intelligence for AI agents & IDEs.

Coding agents working across full-stack and multi-service codebases routinely rebuild existing helpers, trust stale type definitions, and modify API contracts without knowing who consumes them.

Carrick solves this by indexing your entire TypeScript ecosystem, from frontend apps to backend services, whether they live in a monorepo or across multiple repositories. By integrating deeply with the TypeScript compiler, Carrick traces every route, type, and cross-service call while recording function behaviour—so agents search by intent rather than name and stay grounded in your real architecture.

Delivered via MCP for AI agents and LSP for IDEs, Carrick ensures models see existing endpoints and utilities before generating new code. The scanner is source-available, runs from your CLI or CI pipeline, and includes a Free plan so you can start building safer agent workflows immediately.

Get started

npm install -g carrick
carrick init

carrick init signs you in, asks which repositories to index and connects your agent. Your agent then writes each repository's carrick.json and runs the first scan. The quick start has the details (Node 24 or newer).

One index, three surfaces

Search existing code through your agent, inspect live contracts in your editor, and catch breaking changes in your pull requests.

In your agent

Give your AI assistants complete context on what already exists, how endpoints are shaped, and who breaks if something changes. Carrick maps every function by what it actually does, allowing agents to find existing implementations and build on them—even in repositories you haven't checked out locally. Endpoint types are pulled straight from the TypeScript compiler in the service that exposes them.

Works with any MCP-compatible agent, including Claude Code, Cursor, Windsurf, and Codex.

In your editor

Inspect cross-service contracts and jump between connected files without leaving your IDE. "Go to Definition" jumps directly from a service call to its handler when the code is on disk, while Code Lens displays every caller across your local index inline. If a frontend call and backend handler fall out of sync, Carrick surfaces type mismatches as native editor diagnostics.

Available on the Visual Studio Marketplace and Open VSX, or runnable as a standard LSP server.

In your pull request

Bring the exact same index into CI to catch contract risks, duplicate work, and silent version drift. When a producer and consumer fall out of sync—regardless of protocol—Carrick flags the exact mismatch directly on your PR before it merges. It also checks dependency versions across services to catch conflicting package updates early.

Skills

Carrick ships with four skills for the most common agent failures — breaking a caller in another service, rebuilding existing code, trusting a stale copy of another service's type, and missing places in a codebase-wide change. Each skill gets its answer from the Carrick index. carrick init installs them into .claude/skills/ and .agents/skills/.

Skill	Use it	What it returns
carrick-impact	Before changing or deleting a route, handler, response shape, event or shared function, or to ask "who calls this?"	Everything that depends on the code you are about to change, with a file and line for each, and a type verdict for each consumer
carrick-reuse	At the end of a task that added or changed functions, or to ask "does this already exist?"	The new functions compared against the whole function index, and the places the project has built the same thing twice
carrick-drift	Before changing a request or response type, or when a compatibility verdict names a problem you cannot place	The producer's type, each consumer call site's expected type and the stored verdict, side by side, one operation at a time
carrick-census	For "find every place that does X" questions	Every match for two wordings of one concept, paged to the end and joined into one list with a receipt

Ask your agent

• "Which functions handle webhook signing across our services?"
• "Where do we deduplicate users by email?"
• "What calls /api/users, and what response shape does each caller expect?"
• "Show me every function that retries on rate-limit errors."

MCP tools

The MCP endpoint exposes the index as structured tools your agent can call directly. The MCP tools reference lists each tool's parameters and response.

Tool	Purpose
search_by_intent	Search functions by what they do, matching a plain-English query against each function's intent
find_similar	Find similar functions, for code you are about to write or duplicates already in the project
list_function_intents	Browse indexed functions and intents, a page at a time, by service or file
get_project_map	Show the project map, a short summary of services, contracts and unmatched calls
list_projects	List workspace projects and the repositories connected to each
list_services	List the project's services, with their endpoint, call and function counts
get_service_graph	Show the cross-service call graph, with unmatched calls and orphaned endpoints
get_operation	Find who serves and calls an operation, given its method and path
get_callers	Find callers of a function anywhere in the project
get_api_endpoints	List a service's operations across HTTP, GraphQL, WebSockets and pub/sub
get_endpoint_types	Read an endpoint's request and response types as the TypeScript compiler resolved them
get_type_definition	Resolve a named type definition to its expanded TypeScript
check_compatibility	Check a consumer against a producer, with a type verdict for each call
get_service_dependencies	Read npm dependencies and version conflicts, for one service or across the project
list_external_calls	List outbound calls to external targets, such as SDK calls, external domains and env-var URLs
get_contract_pair	Compare consumer and producer types, operation by operation
scaffold	Generate Carrick setup files (the workflow, a Carrick skill, carrick.json and Claude Code hooks)

Keep the index current

The GitHub Action refreshes each repository's part of the index on every push to main. It runs read-only in CI, with no API key to store.

name: Carrick
on:
  push:
    branches: [main]
  pull_request:
    branches: [main]
permissions:
  id-token: write
  contents: read
jobs:
  carrick:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - uses: carrick-tools/carrick@v1

Building the index has the full workflow, with on-demand rescans, dependency installs and monorepo setup.

Docs

• How Carrick works
• What Carrick covers
• carrick.json
• CLI
• MCP tools
• Task skills
• In your editor
• PR comments

Licence

Carrick has a free tier, and paid plans are on the pricing page. The scanner in this repository is source-available under the Elastic License 2.0. Copyright (c) 2026 Far Harbour B.V.

Development

See AGENTS.md for build, test, and contribution conventions.

cargo test
cargo fmt
cargo clippy

Install the optional pre-commit hook to run formatting and tests before each commit:

./scripts/install-hooks.sh