Documentation

Quick Start

Six steps to full API governance. No accounts, no API keys.

npx delimit-cli scan openapi.yaml   # health grade + recommendations
npx delimit-cli try                  # zero-risk demo with sample API

npx delimit-cli setup && source ~/.bashrc

npx delimit-cli init --preset default

npx delimit-cli lint api/openapi.yaml

name: API Contract Check
on: pull_request

jobs:
  api-check:
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - uses: actions/checkout@v4

      - uses: delimit-ai/delimit-action@v1
        with:
          spec: api/openapi.yaml

What is Delimit?

Delimit gives your AI coding assistant persistent memory, governance, and cross-model continuity. It works two ways:

Both run entirely locally. No external services, no accounts, no data leaving your machine.

Enforcement Modes

Delimit has three enforcement modes that control how governance decisions are applied. These work across all AI assistants and the GitHub Action.

Guarded mode is the default. It blocks dangerous operations like destructive deploys while allowing normal development. Switch modes anytime:

# GitHub Action
- uses: delimit-ai/delimit-action@v1
  with:
    spec: api/openapi.yaml
    mode: enforce

# MCP (all assistants)
# Create ~/.delimit/enforcement_mode with: advisory, guarded, or enforce

CLI Reference

The CLI works locally and in any CI system. Install globally or use npx.

npx delimit-cli scan openapi.yaml    # grade a specific spec
npx delimit-cli scan                  # auto-detect specs in current directory

npx delimit-cli try

npx delimit-cli setup              # install into all AI assistants
npx delimit-cli setup --dry-run    # preview what will change

npx delimit-cli init                  # default preset
npx delimit-cli init --preset strict   # all violations are errors
npx delimit-cli init --preset relaxed  # all violations are warnings

npx delimit-cli lint api/openapi.yaml
npx delimit-cli lint api/openapi.yaml --policy strict
npx delimit-cli lint old.yaml new.yaml

npx delimit-cli diff old-api.yaml new-api.yaml

npx delimit-cli explain old-api.yaml new-api.yaml --template migration

npx delimit-cli doctor

npx delimit-cli activate YOUR_LICENSE_KEY

npx delimit-cli uninstall              # remove with backups
npx delimit-cli uninstall --dry-run    # preview removal

Tool Reference

Delimit exposes tools through the MCP protocol. Your AI coding assistant can call any of these directly -- just describe what you want in natural language. The "Say this" column shows example prompts that trigger each tool.

Free tools are unlimited. Pro tools require an active license (deliberation is limited to 3 per month on the free tier).

GitHub Action

Add breaking change detection to any repository. The action runs on every pull request, diffs your OpenAPI spec against the base branch, and posts a comment with breaking changes, semver classification, and a migration guide.

Zero-Config Setup

Delimit auto-detects your OpenAPI spec. No inputs required:

name: API Governance
on: pull_request
jobs:
  check:
    runs-on: ubuntu-latest
    permissions: { pull-requests: write }
    steps:
      - uses: actions/checkout@v4
        with: { fetch-depth: 0 }
      - uses: delimit-ai/delimit-action@v1

Full Configuration

name: API Contract Check
on: pull_request

jobs:
  api-check:
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - uses: actions/checkout@v4

      - uses: delimit-ai/delimit-action@v1
        with:
          # Single file mode -- auto-fetches base branch version
          spec: api/openapi.yaml

          # Or explicit comparison mode
          # old_spec: api/openapi-base.yaml
          # new_spec: api/openapi.yaml

          # Mode: advisory (default) or enforce
          mode: advisory

          # Policy: path to custom policy file or preset name
          # policy: .delimit/policies.yml
          # policy: strict

Input Reference

* Provide either spec alone, or both old_spec and new_spec.

Policy Presets

Delimit ships with 3 built-in presets that control how violations are treated.

Custom Policies

Create .delimit/policies.yml to define your own rules:

# .delimit/policies.yml
override_defaults: false

rules:
  - id: protect_v1_api
    name: Protect V1 API
    description: V1 endpoints are frozen
    change_types:
      - endpoint_removed
      - method_removed
      - field_removed
    severity: error
    action: forbid
    conditions:
      path_pattern: "^/v1/.*"
    message: "V1 API is frozen. Changes must be made in V2."

  - id: warn_response_type_change
    name: Warn Response Type Changes
    change_types:
      - type_changed
    severity: warning
    action: warn
    conditions:
      path_pattern: ".*:2\\d\\d.*"
    message: "Type changed at {path} - verify client compatibility."

Available Change Types

Semver Classification

Delimit deterministically classifies every diff into a semver bump:

• major -- any breaking change detected
• minor -- additive changes only (new endpoints, optional fields)
• patch -- non-functional changes only (descriptions)
• none -- no changes detected

Supported Formats

• OpenAPI 3.0 and 3.1
• Swagger 2.0
• YAML and JSON spec files

Don't Have an OpenAPI Spec?

Many teams don't maintain an explicit API spec. Delimit can help:

npx delimit-cli zero-spec ./src

FAQ

npx delimit-cli uninstall

Links