Drop trailing slash from PostHog MCP URL - #9
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PostHog's MCP endpoint returns HTTP 404 with a JSON-RPC "Not found" error when given https://mcp.posthog.com/mcp/ — the trailing slash hits a path the application layer doesn't route. Without it, the endpoint responds with valid JSON-RPC errors (auth + protocol-aware), confirming the no-slash form is the correct URL. Live config.yaml on the volume was patched in-place via sed; this keeps future cold deploys from re-injecting the bad URL. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
The PostHog MCP URL baked into `docker/entrypoint.sh` had a trailing slash (`https://mcp.posthog.com/mcp/\`) which routes to a 404 at the application layer. Same URL without the slash reaches the JSON-RPC endpoint correctly.
Verification
From a live Railway shell against the running PostHog MCP endpoint:
The no-slash form is the correct route.
Hermes was logging the failure as `MCP server 'posthog' initial connection failed ... unhandled errors in a TaskGroup (1 sub-exception)` — the underlying HTTPStatusError is wrapped inside an anyio TaskGroup and the WARNING-level log doesn't unwrap it. Worth a separate Hermes-upstream fix later to surface `BaseExceptionGroup.exceptions[0]` in MCP connection-failure warnings.
Out of scope
Test plan
🤖 Generated with Claude Code
Summary by cubic
Dropped the trailing slash from the PostHog MCP URL in
docker/entrypoint.shso it points to the JSON-RPC endpoint instead of a 404. Fixes startup connection failures and ensures future deploys inject the correct URL.Written for commit 6c3f8da. Summary will update on new commits.