## Why
MCP error-code telemetry special-cased Codex Apps: its reported error
codes were retained, while codes from every other MCP server were
replaced with `unknown`. Error reporting should behave consistently for
every MCP server. The server name already identifies where an error came
from, so telemetry does not need a separate Codex Apps classification.
This follows up on [#28976](https://github.com/openai/codex/pull/28976),
which introduced MCP error-code telemetry.
## What changed
- Add the MCP server name to call, duration, and error metrics.
- Retain bounded, sanitized tool error codes from every MCP server.
- Remove `McpErrorCodeSource` and the Codex Apps ownership lookup from
telemetry collection.
- Use the same metric-tagging path for blocked, rejected, and executed
MCP calls.
## Test plan
- Verify the complete metric tag set includes the sanitized MCP server
name.
- Verify error codes from ordinary MCP servers are retained, bounded,
and sanitized.
- Preserve coverage for request failures, tool-result failures, nested
auth failures, and span attributes.
[Codex Thread
019edc37-5345-7272-92c9-bf5494cf3819](https://codex-thread-link.openai.chatgpt-team.site/thread/019edc37-5345-7272-92c9-bf5494cf3819)
## Summary
- count MCP `CallToolResult.isError` responses as failed calls instead
of successful transport-level calls
- add `codex.mcp.call.error` with bounded `error_type` and trusted
plugin-service `error_code` dimensions
- record the same error classification on MCP tool-call spans while
keeping untrusted server error text out of metric labels
## Scope
- no changes to MCP routing, retries, tool behavior, configuration, or
public APIs
- request failures remain grouped as `mcp_request`; separating
connection, timeout, protocol, and JSON-RPC failures requires preserving
typed errors through the existing flattened error boundary
## Testing
- `just test -p codex-core 'mcp_tool_call::tests::'` (75 passed)
- `just fix -p codex-core`
- `just fmt`
- `just test -p codex-core` (2,676 passed; 80 unrelated environment
failures from missing test binaries, sandbox signals, and read-only
paths)
Ahmed Ibrahim