MCP Server

LicenseGuard

io.github.rccaoki-wq/license-guard
Developer Tools Legal & Compliance Public & reachable MCP 2025-11-25

What this MCP does

Analyzes open-source dependency licenses and identifies obligations for individual packages or complete manifests.

check_dependency_license
Check one dependency for license obligations
Determine whether adding or keeping a single open source dependency creates a legal obligation, given how this project ships. Call this BEFORE adding a new dependency to a project, and when auditing an existing one. A permissive result means no source-disclosure duty; a blocked result means the license obligates you and the dependency should be replaced or the shipping model reconsidered.
Read only Open world Idempotent
Input schema
{'type': 'object', 'required': ['ecosystem', 'name', 'distribution_model'], 'properties': {'name': {'type': 'string', 'description': 'Package name as written in the manifest, e.g. "express", "requests", "github.com/gin-gonic/gin", or "serde".'}, 'scope': {'enum': ['runtime', 'dev', 'build', 'test', 'optional'], 'type': 'string', 'description': 'Where the dependency sits. Use "dev", "build", or "test" for anything that does not end up in the shipped artifact — those carry no distribution obligation. Defaults to "runtime".'}, 'version': {'type': 'string', 'description': 'Exact version if known. Omit to use the latest published version, which may differ from what is installed.'}, 'ecosystem': {'enum': ['npm', 'pypi', 'go', 'cargo', 'rubygems', 'nuget'], 'type': 'string', 'description': 'Package registry the dependency comes from.'}, 'distribution_model': {'enum': ['saas', 'distributed-binary', 'on-prem-delivery', 'internal-only', 'library-published'], 'type': 'string', 'description': 'How the software incorporating this dependency reaches its users. This determines the answer: "saas" = users reach it over a network; "distributed-binary" = shipped as an app or binary; "on-prem-delivery" = installed in a customer environment; "internal-only" = never leaves your organization; "library-published" = released for others to depend on.'}}}
Output schema
{'type': 'object', 'required': ['license', 'verdict', 'obligations', 'rationale'], 'properties': {'license': {'type': ['string', 'null']}, 'verdict': {'enum': ['allowed', 'review', 'blocked'], 'type': 'string'}, 'rationale': {'type': 'string'}, 'reference': {'type': 'string'}, 'assumption': {'type': 'object', 'required': ['declared', 'assumed'], 'properties': {'assumed': {'type': 'string'}, 'declared': {'type': 'string'}}}, 'obligations': {'type': 'array', 'items': {'type': 'string'}}}}
check_manifest_licenses
Check a whole manifest
Scan an entire dependency manifest and report every dependency whose license creates an obligation for this shipping model. Use when reviewing a project as a whole, preparing for due diligence, or after a large dependency change. Pass a package-lock.json when one exists: problematic licenses usually arrive as transitive dependencies rather than ones you added directly, and only a lockfile reveals those.
Read only Open world Idempotent
Input schema
{'type': 'object', 'required': ['content', 'distribution_model'], 'properties': {'content': {'type': 'string', 'description': 'Full text of a lockfile, SBOM, or manifest. Accepted: package-lock.json, pnpm-lock.yaml, yarn.lock, go.sum, Cargo.lock, poetry.lock, uv.lock, Gemfile.lock, packages.lock.json, CycloneDX (JSON), SPDX (JSON), package.json, requirements.txt, go.mod, Cargo.toml, .csproj, Directory.Packages.props, packages.config. The format is detected automatically. Prefer a lockfile: it covers transitive dependencies and carries exact versions. package-lock.json is best of all, since it embeds licenses and needs no registry lookups. An SBOM covers several ecosystems in one document, but its licenses are read from the document rather than looked up, so they are only as current as the document.'}, 'distribution_model': {'enum': ['saas', 'distributed-binary', 'on-prem-delivery', 'internal-only', 'library-published'], 'type': 'string', 'description': 'How the software incorporating this dependency reaches its users. This determines the answer: "saas" = users reach it over a network; "distributed-binary" = shipped as an app or binary; "on-prem-delivery" = installed in a customer environment; "internal-only" = never leaves your organization; "library-published" = released for others to depend on.'}}}
Output schema
{'type': 'object', 'required': ['summary', 'findings', 'limitations'], 'properties': {'summary': {'type': 'object', 'required': ['total', 'allowed', 'review', 'blocked'], 'properties': {'total': {'type': 'number'}, 'review': {'type': 'number'}, 'allowed': {'type': 'number'}, 'blocked': {'type': 'number'}}, 'description': 'Counts by verdict. total is every dependency found, not only the ones that were resolved.'}, 'findings': {'type': 'array', 'items': {'type': 'object', 'required': ['ecosystem', 'name', 'scope', 'verdict', 'obligations', 'rationale'], 'properties': {'name': {'type': 'string'}, 'scope': {'enum': ['runtime', 'dev', 'build', 'test', 'optional'], 'type': 'string'}, 'verdict': {'enum': ['allowed', 'review', 'blocked'], 'type': 'string'}, 'version': {'type': ['string', 'null']}, 'ecosystem': {'type': 'string'}, 'rationale': {'type': 'string'}, 'obligations': {'type': 'array', 'items': {'type': 'string'}}, 'resolvedFrom': {'type': 'string', 'description': 'Where the license came from. "lockfile" is exact; "sbom" means it was written in the SBOM you pasted rather than looked up, so it is only as current as that document; "registry" and "deps-dev" are the pinned version as published; "registry-latest" means the pinned version could not be read and the latest release was used instead; "not-checked" means the lookup budget ran out and this dependency was never resolved; "not-published" means it is a git dependency, a member of the scanned workspace, or from a private registry, so no public registry has license data for it — re-scanning will not resolve those.'}, 'spdxExpression': {'type': ['string', 'null']}}}}, 'ecosystem': {'type': 'string'}, 'limitations': {'type': 'array', 'items': {'type': 'string'}, 'description': 'What this scan could not establish. Never empty when anything was left unresolved. Read it before treating a result as clean.'}, 'distributionModel': {'type': 'string'}}}
explain_license
Explain what a license requires
Given an SPDX license identifier or expression, explain what it requires across every shipping model at once. Use when the question is about the license itself rather than a specific package — for example when comparing AGPL-3.0 against GPL-3.0 for a hosted service, or deciding what a project may safely depend on.
Read only Open world Idempotent
Input schema
{'type': 'object', 'required': ['license'], 'properties': {'license': {'type': 'string', 'description': 'SPDX identifier or expression, e.g. "AGPL-3.0-only", "Apache-2.0", or "(MIT OR GPL-2.0-only)".'}, 'linkage': {'enum': ['dynamic', 'static', 'separate-process'], 'type': 'string', 'description': 'How the dependency is linked. Matters for LGPL-family licenses. Compiled languages such as Go and Rust normally link statically. Defaults to "dynamic".'}}}
Output schema
{'type': 'object', 'required': ['license', 'byDistributionModel', 'devScope'], 'properties': {'license': {'type': 'string'}, 'linkage': {'type': 'string'}, 'devScope': {'type': 'object', 'required': ['verdict', 'rationale'], 'properties': {'verdict': {'enum': ['allowed', 'review', 'blocked'], 'type': 'string'}, 'rationale': {'type': 'string'}}, 'description': 'The result when the dependency never reaches users (dev, build or test scope). Independent of the shipping model.'}, 'byDistributionModel': {'type': 'array', 'items': {'type': 'object', 'required': ['model', 'verdict', 'obligations', 'rationale'], 'properties': {'model': {'enum': ['saas', 'distributed-binary', 'on-prem-delivery', 'internal-only', 'library-published'], 'type': 'string'}, 'verdict': {'enum': ['allowed', 'review', 'blocked'], 'type': 'string'}, 'rationale': {'type': 'string'}, 'obligations': {'type': 'array', 'items': {'type': 'string'}}}}, 'description': 'One row per way of shipping. This is where the same license diverges.'}}}
Added
explain_license
Sept. 17, 2026, 12:49 p.m.
Added
check_manifest_licenses
Sept. 17, 2026, 12:49 p.m.
Added
check_dependency_license
Sept. 17, 2026, 12:49 p.m.