create_track

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description must carry the transparency burden. It provides useful lifecycle context: built-in tracks are pre-existing, and track creation alone does not grant tester access or ship a release. However, it does not mention permission requirements, default commit behavior, validate_only effects, or what a successful response looks like.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three concise sentences, front-loaded with the core action. Every sentence earns its place: what the tool does, when it is unnecessary, and what to do next. No redundant or vague phrasing.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Despite having no output schema or annotations, the description is mostly complete for selection and invocation: it specifies the track type, excludes built-in tracks, and explains the required follow-up steps. Minor gaps remain around commit/review semantics, but the schema documents those parameters.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, and the parameter descriptions already explain track, form_factor, package_name, validate_only, and changes_not_for_review. The tool description adds useful workflow context but no additional parameter-specific semantics, so the schema-driven baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the action and resource: 'Create a new custom closed testing track.' It also distinguishes this tool from alternatives by noting built-in tracks already exist and cannot/should not be created, and by separating it from create_release.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly states when to use the tool (creating a new custom closed testing track), when not to use it (built-in tracks already exist), and the follow-up workflow: use update_testers for Google Groups access and create_release to ship. This is strong practical guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.