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

The description states each call moves the baseline forward and a show is reported only once, i.e. repeated identical calls return different results and mutate server state. This directly contradicts the idempotentHint=true and readOnlyHint=true annotations, so the annotations misrepresent the actual behavior.

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?

Two sentences, front-loaded with the core result set and followed by the crucial behavioral caveat. No filler; every clause earns its place.

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 no output schema, the description explains what is returned (newly matched podcasts and their contact route), the auth requirement, and the scoping option. It is nearly complete, though it does not describe ordering or how many results to expect.

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?

With a single parameter and 100% schema description coverage, the schema already fully documents watch_id, including its default behavior. The description's reference to 'one, by watch_id' and watch_podcast_topic adds only marginal value, matching the baseline of 3.

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 states a specific verb and resource: it returns the podcasts that newly match a topic watch, with their best contact route. It clearly distinguishes itself from sibling tools like watch_podcast_topic (creates watches) and find_podcast_contacts (contact lookup).

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 gives a clear precondition ('Signed-in accounts') and scoping guidance (all watches by default, or one via watch_id). It lacks explicit when-not / alternative routing, so it falls short of a 5.

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