podcast_by_guid

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

Annotations already declare readOnlyHint=true, indicating read-only behavior. The description does not add additional behavioral context beyond 'look up', which is consistent with the annotation. No contradictions, but no extra behavioral traits are disclosed.

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 two sentences, front-loading the main purpose and then providing usage guidance. Every word is necessary and there is no redundancy.

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 simple lookup tool with one parameter and no output schema, the description is mostly complete. It explains what the tool does, when to use it, and the parameter meaning. It does not describe the return value, but that is acceptable given the simplicity and context from siblings.

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?

The schema provides 100% coverage with a description for the guid parameter. The description adds semantic meaning by explaining that the GUID is 'the globally unique identifier defined in the Podcast Namespace spec', which goes beyond the schema's terse description.

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 the tool looks up a podcast by its GUID, a specific identifier. It distinguishes from siblings by specifying that it uses the GUID rather than feed URL or ID, which is explicit and differentiates it from similar tools.

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 this tool: when you have the GUID rather than a feed URL or ID. This provides clear guidance on when to choose this tool over alternatives like podcast_by_feed_url or podcast_by_feed_id.

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