promote_release

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

The description discloses key side effects: 'This replaces the destination track's release list' and explains rollout statuses ('completed'/'inProgress'). It also clarifies the effect of validate_only, ensuring the agent understands the operation is destructive and verifiable. Since no annotations are present, this additional detail is valuable.

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 sentences, front-loads the primary action, and contains no fluff. Every clause adds information: version codes, user_fraction semantics, the replacement behavior, and the validation tip are all high-value.

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?

For a tool with 10 parameters and nested objects, the description covers the crucial decisions (full vs staged rollout, validate_only) and the core destructive nature. It doesn't enumerate every parameter (schema does that), but it creates a coherent mental model. Missing details like error handling or rate limits are minor given the schema's completeness.

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?

Although the schema already covers 100% of parameters with descriptions, the tool description adds meaningful inter-parameter logic, such as the relationship between user_fraction and rollout status, and the default behavior for release_name and release_notes. This goes beyond a simple restatement of schema fields.

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 states what the tool does: 'Promote the active release of one track to another' with a concrete example 'beta -> production' and notes it keeps version codes. This is a specific verb-resource pair with scope, effectively distinguishing it from siblings like update_rollout or halt_rollout.

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?

It explains when to use full rollout (omit user_fraction) vs staged rollout (pass user_fraction) and advises using validate_only first. While it doesn't explicitly contrast with alternative tools like update_rollout, the context of 'matching how promoting works in the Play Console' gives practical guidance.

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