Update Changelog Agent Skill

Update CHANGELOG.md for an ai-projects regeneration

When to Use

• The apply-post-emitter-edits, author-samples, and author-tests skills have all completed.
• A regeneration has produced a meaningful diff in src/ and review/ai-projects-node.api.md.
• You need a CHANGELOG entry before opening the PR.

Inputs

• The api-surface diff JSON (from ../author-samples/prompts/diff-api-surface.prompt.md).
• git diff HEAD -- src/ for context on hand-applied edits and bug fixes.
• The current CHANGELOG.md for voice and section ordering.

Procedure

Run from sdk/ai/ai-projects/.

Step 1: Read the current CHANGELOG style

Open CHANGELOG.md. Note the section ordering used in recent entries:

• ### Breaking Changes
• ### Features Added
• ### Bugs Fixed
• ### Other Changes

Voice examples (copy this voice exactly):

• Features: "Add project.beta.skills route for accessing skills"
• Breaking: "Rename id property in Schedule interface to schedule_id"
• Bugs: "Remove redundant foundryFeatures property from EvaluationRulesCreateOrUpdateOptionalParam"
• Other: "Deprecated TextResponseFormatConfiguration in favor of TextResponseFormat"

Step 2: Classify changes

For each item from the api-surface diff plus each hand-applied edit:

| Bucket | What goes here |

|--------|----------------|

| Breaking Changes | Removed/renamed public symbols; required→optional or optional→required; method signature changes; namespace renames. |

| Features Added | New public classes, methods, namespaces, interfaces. |

| Bugs Fixed | Behavioral fixes; redundant-property removals; correctness fixes from post-emitter workarounds. |

| Other Changes | Deprecations, internal refactors, dependency bumps. |

Beta-namespace additions still go under Features Added, with the namespace path included (e.g., project.beta.toolboxes).

When a new public method or route brings supporting request/response models, helper classes, union members, or enum values along with it, do not enumerate every supporting type in the changelog. List the new public method/route and mention the feature it enables. Only call out supporting types separately when they are independently user-facing concepts that customers would reasonably search for outside the method they support.

Step 3: Insert or extend the top entry

First, inspect the current top entry in CHANGELOG.md:

• If it is already an ## <version> (Unreleased) (or otherwise unreleased) entry, do not create a new entry and do not bump the version. Instead, merge the new items into the existing buckets under that entry — adding new bullets, keeping the existing ones, and dropping any subsection that ends up empty. Skip Step 3.5 entirely in this case (the package.json version already matches).
• Only if the current top entry is a released version (i.e. its header has a date, not (Unreleased)) do you create a new top entry. Use templates/changelog-entry.md and insert it directly above that released entry.

When creating a new entry, pick a tentative next version following semver against the previous CHANGELOG entry:

• Breaking Changes present → bump major (e.g., 2.1.0 → 3.0.0).
• Features Added only → bump minor (e.g., 2.1.0 → 2.2.0).
• Bugs Fixed / Other Changes only → bump patch (e.g., 2.1.0 → 2.1.1).

Use the header form ## <new-version> (Unreleased) so the release engineer just has to swap Unreleased for a date.

Drop empty subsections (don't leave a ### Bugs Fixed heading with no items underneath).

Step 3.5: Sync package.json version

Skip this step if you merged into an existing (Unreleased) entry in Step 3 — the version did not change, so package.json is already correct.

When you created a new top entry, the version field in package.json MUST match the version in that new entry. Update package.json to match (e.g., "version": "2.2.0"). Release tooling fails CI if these drift.

Step 4: Validate

• The CHANGELOG still parses (npx prettier --check CHANGELOG.md).
• No duplicate items across buckets.
• Each line is a single bullet starting with a verb in the same tense as nearby entries.
• package.json version field matches the top CHANGELOG entry's version (run node -p "require('./package.json').version" and compare).

Hand-off

Done. Hand off to open-regeneration-pr.