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

Annotations already declare the safety profile (destructiveHint=true, idempotentHint=true, readOnlyHint=false), and the description adds real value: it discloses that only the name changes, that no_changes can be returned (corroborating idempotency), and that the previous name is not returned. The only gap is that it doesn't explain why a rename is flagged destructive or whether any downstream state is affected.

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?

Front-loaded with the action and the usage condition, with the alternative tools noted early. The final sentence is a dense return-shape dump that would read better as a list, but every clause carries information.

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?

With no output schema, the description usefully spells out the returned fields and the status values, which is the main completeness requirement here. The remaining gap is the unexplained project_id semantics and the reason for the destructive flag.

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 coverage is only 33%, but the description compensates by naming the source of feed_id (list_feeds / create_feed) and explicitly marking project_id as OPTIONAL. It adds little about why project_id exists or what it scopes, so it is not fully complete.

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?

"Rename a feed" gives a specific verb and resource, and the follow-up sentence clarifies the exact scope (name only). It is clearly distinguishable from siblings like set_feed_settings, pause_feed, and set_ad_name/set_marketplace_name.

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?

Explicitly states the trigger condition ("when the user wants a feed to have a different name") and names the alternatives for adjacent intents ("pause_feed / resume_feed handle enabling"), so the agent knows both when to use it and when not to.

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