refactor(agents): simplify mergeTelemetry implementation

[zrosenbauer]

Summary

• Extract the "funkai.agentChain" magic string into an AGENT_CHAIN_METADATA_KEY constant for clarity and single-source-of-truth
• Replace mutable merged variable + isNil guard with a direct return using nullish coalescing (??) for functionId
• Net reduction of 2 lines; no behavioral change

Test plan

• pnpm typecheck --filter=@funkai/agents passes
• pnpm test --filter=@funkai/agents — all 665 tests pass

[changeset-bot]

🦋 Changeset detected

Latest commit: a11fd3f

The changes in this PR will be included in the next version bump.

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Project	Deployment	Actions	Updated (UTC)
funkai	Ready	Preview, Comment	Apr 2, 2026 10:20pm

[coderabbitai]

📝 Walkthrough

Walkthrough

Added a changeset configuration file and refactored the resolveTelemetry function to compute the merged telemetry object directly, set functionId via nullish-coalescing, and replace the string literal metadata key "funkai.agentChain" with a named constant while preserving existing control flow.

Changes

Cohort / File(s)	Summary
Changeset Configuration .changeset/telemetry-cleanup.md	New changeset file with YAML frontmatter markers only.
Telemetry Refactoring packages/agents/src/core/agents/base/telemetry.ts	Refactored resolveTelemetry to compute merged telemetry directly, use nullish-coalescing for functionId assignment, and replace string literal "funkai.agentChain" with AGENT_CHAIN_METADATA_KEY constant. Control flow and ancestry serialization format unchanged.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• #65 — Agent telemetry handling with functionId and agent-chain metadata management
• #75 — Direct continuation refactoring the same resolveTelemetry implementation with nullish-coalescing and constant-based metadata key
• #50 — Introduction and propagation of agentChain ancestry data in telemetry

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main refactoring in the changeset: simplifying the mergeTelemetry (or resolveTelemetry) implementation through code restructuring.
Description check	✅ Passed	The description is directly related to the changeset, detailing the specific refactoring changes made: extracting a magic string constant, replacing mutable variables with nullish coalescing, and confirming test coverage.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/agents/src/core/agents/base/telemetry.ts`:
- Around line 6-7: The JSDoc for the AGENT_CHAIN_METADATA_KEY constant is
currently a single-line block causing the jsdoc-js(multiline-blocks) warning;
update the comment above AGENT_CHAIN_METADATA_KEY to a multiline JSDoc block by
expanding it into the standard /* * ... */ multi-line form (i.e., start /** on
its own line, put the description on the next line prefixed with *, and close */
on its own line) so the symbol AGENT_CHAIN_METADATA_KEY in telemetry.ts uses a
multiline JSDoc comment.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro

Run ID: 4de21fe8-092a-422d-add3-0437ee75d560

📥 Commits

Reviewing files that changed from the base of the PR and between 4913e73 and a11fd3f.

📒 Files selected for processing (2)

• .changeset/telemetry-cleanup.md
• packages/agents/src/core/agents/base/telemetry.ts