Include error code and message in the 'Sending response' trace log

[Pujitha Paladugu (pujitha24)]

Motivation:
When a server sends back a JSON-RPC error response, the
'Sending response' trace line only surfaced error.data (when
present) but silently dropped error.code and error.message. A user
debugging a malformed request spent significant time investigating
because the trace output gave no indication that an error had even
occurred, even though the underlying response clearly carried a
-32602 error with a descriptive message.

Approach:
traceReceivedResponse (the client-side counterpart in the same file)
already appends "Request failed: ()." to its main
log line when message.error is set. Apply the identical pattern to
traceSendingResponse so the server-side trace line carries the same
information. This is a pure logging/string-formatting change with no
behavioral or API impact.

Validation:

• npx tsc -b ./jsonrpc/tsconfig.json and npx tsc -b tsconfig.json
  (full monorepo) both compile cleanly.
• npm run lint (eslint) in jsonrpc/ passes with no new warnings.
• Added a test, "Trace includes error code and message when sending
  an error response", to jsonrpc/src/node/test/connection.test.ts.
  Ran npm run test:node in jsonrpc/: 68 passing, including the new
  test. Verified the test fails (times out, since the assertion runs
  inside a rejection-handler .then() callback, consistent with this
  file's existing test style) against the pre-fix code and passes
  against the fix.
• Did not run the jsonrpc browser test suite (npm run test:browser)
  in this environment: it requires downloading a Playwright Chrome
  binary, which failed here due to local disk space constraints. The
  browser tests exercise the same shared
  jsonrpc/src/common/connection.ts trace code path, so this is a
  disclosed gap rather than a skipped check.

Report: #1604
Signed-off-by: Pujitha Paladugu 10557236+pujitha24@users.noreply.github.com
Assisted-by: claude-sonnet-5 (via Claude Code)

Fixes #1604

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[Copilot]

🟢 Approval recommended

The focused logging change is tested, with only minor punctuation cleanup outstanding.

Pull request overview

Adds JSON-RPC error details to server-side response traces for easier debugging.

Changes:

• Logs error messages and codes when sending failed responses.
• Adds regression coverage for error-response tracing.

File summaries

File	Description
jsonrpc/src/node/test/connection.test.ts	Tests error details in response traces.
jsonrpc/src/common/connection.ts	Appends error messages and codes to traces.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 1
• Review effort level: Balanced

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[Pujitha Paladugu (pujitha24)]

Good catch, added the missing period so it now reads ...ms.${error}, matching traceReceivedResponse. Ran the jsonrpc node test suite again (68 passing, including the new trace test) to confirm nothing broke.

[Copilot]

Copilot review overview

🟢 Approval recommended

The focused change matches existing trace behavior and includes appropriate regression coverage.

Review effort: Balanced
Findings: None

Resolved since last review (1)

• This emits Processing request took 1ms Request failed... without a sentence boundary. The paired…

[Dirk Bäumer (dbaeumer)]

/AzurePipelines run

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Successfully started running 1 pipeline(s).

[Pujitha Paladugu (pujitha24)]

This is approved with green CI and no outstanding comments as far as I can tell — ready whenever you have a moment. Happy to rebase first if you'd like it freshened.