justin
d5cd602d85
Build & push patched image / build (push) Failing after 1m13s
The wrapper sed-patches the two host-wide OAuth 2.1 discovery route registrations in MetaMCP's compiled backend bundle so spec-compliant MCP clients do not force an interactive login flow on public endpoints. See README for full rationale (RFC 9728, MCP Authorization spec 2026-03-26 revision) and the diagnostic evidence. Guarded with grep pre/post-conditions so a future upstream release that renames or restructures these routes fails the build loudly rather than silently shipping an unpatched image.
100 lines
3.6 KiB
Markdown
100 lines
3.6 KiB
Markdown
# metamcp-patched
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A thin wrapper around [`ghcr.io/metatool-ai/metamcp`](https://github.com/metatool-ai/metamcp)
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that hides the host-wide OAuth 2.1 discovery endpoints so spec-compliant MCP
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clients don't force an interactive login on public endpoints.
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## The problem this fixes
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MetaMCP unconditionally publishes RFC 9728 protected-resource metadata and
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RFC 8414 authorization-server metadata at:
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- `/.well-known/oauth-protected-resource`
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- `/.well-known/oauth-authorization-server`
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Both documents describe the whole MetaMCP host as OAuth-protected — even
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if every configured endpoint is public. Per the MCP Authorization spec
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(2026-03-26 revision), a spec-compliant client — Claude.ai's remote-MCP
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integration, Claude Desktop, and the reference SDKs — probes these paths
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on connect. When it sees them, it kicks off the OAuth flow (with dynamic
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client registration and PKCE) **before** calling any tool. Users get an
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interactive login page even when trying to connect to an endpoint that
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doesn't require auth.
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The route mounts live in a compiled bundle with no env-var gate — the
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line `app.use(oauth_default)` in `apps/backend/dist/index.js` pulls the
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metadata router in unconditionally. There is no admin toggle for it in
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the shipping build.
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This repo produces a wrapper image that sed-patches the two discovery
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route registrations to bogus paths, so Express falls through to its
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default 404 for those requests. Nothing else in MetaMCP changes.
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Endpoints that DO enforce auth still 401 correctly; they just can't be
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consumed via OAuth dynamic-discovery clients any more (consume them via
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a bearer token in the MCP client's config instead).
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## Using the pre-built image
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```yaml
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# docker-compose.yml
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services:
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metamcp:
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image: git.jpaul.io/justin/metamcp-patched:latest
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pull_policy: always
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# ... rest of your existing metamcp service config unchanged
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```
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## Or build from source locally
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```yaml
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services:
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metamcp:
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image: metamcp-patched:local
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pull_policy: never
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build:
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context: https://git.jpaul.io/justin/metamcp-patched.git
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# or a local clone / vendored path
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```
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Bump upstream at any time with:
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```bash
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docker compose build --pull metamcp && docker compose up -d metamcp
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```
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The Dockerfile has `grep` guards that fail the build loudly if a future
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upstream release renames or restructures the OAuth routes, so a bad bump
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never silently ships an unpatched image.
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## Verify it worked
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```bash
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UA="Mozilla/5.0 (X11; Linux x86_64) Firefox/120.0"
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# want 404, was 200 pre-patch
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curl -sSo /dev/null -w "%{http_code}\n" -H "User-Agent: $UA" \
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"https://<your-metamcp-host>/.well-known/oauth-protected-resource"
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curl -sSo /dev/null -w "%{http_code}\n" -H "User-Agent: $UA" \
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"https://<your-metamcp-host>/.well-known/oauth-authorization-server"
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# want 200 (unchanged) — proves you didn't collaterally break the endpoint
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curl -sSo /dev/null -w "%{http_code}\n" -H "User-Agent: $UA" \
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-H "Accept: application/json, text/event-stream" \
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-X POST -H "Content-Type: application/json" \
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-d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":{},"clientInfo":{"name":"diag","version":"1.0"}}}' \
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"https://<your-metamcp-host>/metamcp/<a-public-endpoint>/mcp"
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```
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## Delete this repo the day upstream ships a toggle
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The right fix belongs in MetaMCP itself — either an env var like
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`DISABLE_OAUTH_DISCOVERY=true`, or per-endpoint RFC 9728 metadata
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scoping so public endpoints don't advertise. Track upstream at
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<https://github.com/metatool-ai/metamcp>.
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## License
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MIT for the wrapper contents (Dockerfile, workflow, docs). The base
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image and everything it contains remain under their upstream licenses.
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