About guardfile
guardfile checks supplied repository files for four contribution guardrails: DCO, CLA, changesets, and sign-off. It returns a report with evidence paths, missing checks, and an overall completeness flag, using only the provided content.
Key features
- 01Detect DCO, CLA, changesets, and sign-off
- 02Match guardrails by file path or content
- 03List sorted evidence paths without duplicates
- 04Report present and missing checks
- 05Validate input locally
Use cases
- 01Check contribution requirements before a release
- 02Review repository files for guardrail evidence
- 03Identify missing DCO, CLA, changeset, or sign-off rules
MCP support
The MCP server exposes an `extract_guardrails` tool that accepts repository-relative paths and file contents, then returns detected guardrails, evidence, missing items, and completeness.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
Tools
1Saved tool list · updated 1w ago
| Parameter | Type | Required | Description |
|---|---|---|---|
| files | array | Yes | Repo files to inspect (at least one) |
Details
From the project READMEguardfile
A repo can claim all sorts of contribution guardrails — sign your commits, agree to the licence terms, add a changeset — but the claim only means something if you can point at the files that put each one in force. guardfile does that pointing: you hand it a repo's files, and it hands back one checkable report of which guardrails are actually present, with the evidence for each.
Four guardrails are detected, by fixed rules:
- DCO — a file whose basename is exactly
DCO(any case), or any content naming the Developer Certificate of Origin. - CLA — a file whose basename starts with
CLA(any case, as inCLA.md), or any content naming the Contributor License Agreement. - changesets — a path containing
.changeset/, a path ending in/.changeset, a path that is exactly.changeset, or any content naming the@changesets/scope. - sign-off — any content carrying a
Signed-off-by:line. The colon is part of the rule: a bareSigned-off-bymention does not count.
All content matching is case-insensitive. For each
guardrail the report lists the paths that triggered it,
sorted, with each path appearing at most once even when a
single file triggers the same guardrail by both its path
and its content. Alongside the four verdicts the report
gives the number present, the names of the ones missing
(in the fixed order dco, cla, changeset, signoff), and a
complete flag that is true only when all four are
present.
Malformed input — a missing or empty file list, an entry
that is not an object, a missing, empty, or duplicated
path, or content that is missing or not a string — is a
validation error naming the offending path (for example
files[1].content must be a string), and no partial
report is produced. The computation is pure and local: no
network, no configuration, and no files read beyond the
input you pass in.
CLI
npx @reneturcios/guardfile extract --input args.json
npx @reneturcios/guardfile --version
args.json contains the full arguments object:
{
"files": [
{ "path": "DCO", "content": "Developer Certificate of Origin\n\nVersion 1.1" },
{ "path": "docs/contributing.md", "content": "Please add a Signed-off-by: line." },
{ "path": ".changeset/bright-foxes-jump.md", "content": "---\n\"pkg\": patch\n---\n" }
]
}
The report is printed as JSON:
{
"guardrails": {
"dco": { "present": true, "evidence": ["DCO"] },
"cla": { "present": false, "evidence": [] },
"changeset": { "present": true, "evidence": [".changeset/bright-foxes-jump.md"] },
"signoff": { "present": true, "evidence": ["docs/contributing.md"] }
},
"present_count": 3,
"missing": ["cla"],
"complete": false
}
Exit codes: 0 on success, 1 on a runtime error
(including an unreadable or invalid input file, or invalid
input), 2 on a usage error.
MCP server
npx -y @reneturcios/guardfile mcp
MCP client config:
{
"mcpServers": {
"guardfile": {
"command": "npx",
"args": ["-y", "@reneturcios/guardfile", "mcp"]
}
}
}
Tools
-
extract_guardrails— Extract a repo's guardrails from its files.files(array, required, at least one) — repo files as{path, content}objects;pathis a repo-relative path unique across the set andcontentis the file's content, which may be empty
Returns
{guardrails, present_count, missing, complete}.
Docker
docker run -i ghcr.io/cloudcorprecords/guardfile
docker run --rm -v "$PWD:/w" ghcr.io/cloudcorprecords/guardfile extract --input /w/args.json
Development
npm install
npm run build # tsc -> dist/
npm test # tsx --test test/*.test.ts (pure local, no network)
npm run dev # run the CLI from source
License
MIT — Copyright (c) 2026 Rene Turcios
Comments
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