Add a podcast to the index

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

The description discloses critical behavior beyond what annotations already provide: writes to a public global directory read by many apps, has no removal path, returns existing id if already indexed, and fails cleanly without write permission. These details align with destructiveHint=true and idempotentHint=true, and add significant operational context.

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?

Four sentences, each carrying distinct, necessary information: core action, public/irreversible effect, idempotent behavior, and auth requirement. It is front-loaded with the main purpose and contains no filler.

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?

The description covers action, prerequisites, irreversibility, idempotency, and auth failure behavior. Without an output schema, it does not explicitly state what a successful new submission returns, though it implies an id is returned. This small gap prevents a perfect score.

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 description coverage is 100%, with confirm, feed_url, and url all documented. The description repeats the confirm requirement and adds auth context but does not explain the url alias beyond what the schema already says, so it adds little beyond the baseline.

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 opens with a specific verb and resource: 'Add a podcast to Podcast Index by its RSS feed URL.' This clearly states what the tool does and implicitly distinguishes it from the sibling tool submit_feed_by_itunes_id, which uses a different input identifier.

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 gives clear usage context: it requires confirm: true, needs a separate write-permission API key, and is irreversible. It does not explicitly name alternatives like submit_feed_by_itunes_id or state when not to use this tool, but the context is strong enough for an agent to infer the appropriate scenario.

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