Update a local post

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

Beyond annotations (readOnlyHint=false, idempotentHint=true, etc.), the description discloses the updateMask partial-update behavior, ALERT rejection risk, rate limit, legacy v4 API constraint, and return value. This is rich context that annotations alone do not provide. No contradiction with annotations.

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 dense but every sentence provides actionable information: patch semantics, field structure, restrictions, rate limit, API compatibility. No filler words or redundant repetition of schema content. Appropriately front-loaded with the core action and key constraint.

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 complex tool with 5 required params, nested objects, and no output schema, the description is complete: it explains the updateMask behavior, nested field hierarchy, required fields for EVENT/OFFER, media format, ALERT restrictions, rate limit, and legacy API context. An agent has all needed information to invoke it correctly.

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 schema covers each top-level parameter (100% coverage), the description adds substantial meaning for nested objects (callToAction, event, offer, media) with allowed values, required conditions, and examples for updateMask. This goes far beyond the schema's minimal descriptions, especially for the unstructured 'post' object.

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 'Updates fields of an existing local post' with a specific verb and resource, and distinguishes it from sibling tools like create_local_post and delete_local_post by emphasizing 'existing' and the PATCH/updateMask mechanism. The scope is unambiguous.

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 implies usage for existing posts and gives important context: ALERT posts are restricted/rejected and the 10 edits/min cap. It does not explicitly name alternatives like create_local_post for new posts, but the distinction is clear enough for an agent. Lacking explicit 'when not to use' but context is strong.

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