io.github.oasdiff/oasdiff

Official4 tools

oasdiff

Detect breaking changes, generate changelogs, diff, and validate OpenAPI specs.

Detects breaking changes and generates changelogs for OpenAPI specifications.

Captured live from the server via tools/list.

oasdiff_breaking_changes

Detect breaking API changes between two OpenAPI specifications. Pass the base (old) and revision (new) specs as YAML or JSON; returns the breaking and warning-level changes. Use this when the question is whether an API change breaks existing clients. Use oasdiff_changelog instead to list every change including non-breaking and informational ones, oasdiff_diff for the raw added/removed/modified structure, or oasdiff_validate to check a single spec rather than compare two. Both specs must be valid, self-contained OpenAPI (external $ref URLs or files are not resolved).

Parameters (2)

basestringrequired
the base (old) OpenAPI specification, as YAML or JSON
revisionstringrequired
the revision (new) OpenAPI specification, as YAML or JSON

oasdiff_changelog

Produce a full changelog of every detected change between two OpenAPI specifications (base vs revision), down to informational changes. Pass both specs as YAML or JSON. Use this when you want the complete set of changes at every severity. Use oasdiff_breaking_changes instead when you only care whether the change is breaking (less noise), or oasdiff_diff for the raw structural diff without a backward-compatibility judgment. Both specs must be valid, self-contained OpenAPI (external $ref URLs or files are not resolved).

Parameters (2)

basestringrequired
the base (old) OpenAPI specification, as YAML or JSON
revisionstringrequired
the revision (new) OpenAPI specification, as YAML or JSON

oasdiff_diff

Show the structural diff between two OpenAPI specifications (base vs revision): what was added, removed, or modified. Pass both specs as YAML or JSON. Use this when you want the raw structural changes rather than a backward-compatibility verdict. Use oasdiff_breaking_changes to judge whether changes break clients, or oasdiff_changelog for a severity-classified changelog. Both specs must be valid, self-contained OpenAPI (external $ref URLs or files are not resolved).

Parameters (2)

basestringrequired
the base (old) OpenAPI specification, as YAML or JSON
revisionstringrequired
the revision (new) OpenAPI specification, as YAML or JSON

oasdiff_validate

Validate a single OpenAPI specification against the OpenAPI and JSON Schema rules. Pass the spec as YAML or JSON; returns the findings (empty when the spec is valid). Use this when you have one spec and want to check it is well-formed. For comparing two specs, use oasdiff_breaking_changes, oasdiff_changelog, or oasdiff_diff instead. The spec must be self-contained (external $ref URLs or files are not resolved).

Parameters (1)

specstringrequired
the OpenAPI specification to validate, as YAML or JSON

Install

claude_desktop_config.json

{
  "mcpServers": {
    "oasdiff": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://api.oasdiff.com/mcp"
      ]
    }
  }
}

Desktop config is stdio-only; this bridges via mcp-remote. Native remote: Settings > Connectors.