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

Adds substantial behavior beyond the annotations: signature verification scheme (X-Tango-Signature = 'sha256=' + hmac_sha256(secret, raw_body)), the secret's exactly-once reveal on first call with a do-not-repeat-in-chat warning, that later calls never re-reveal it, and that rotation immediately invalidates the previous secret. This is exactly the context an agent needs to avoid leaking or bricking a credential.

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 purpose before the mechanics, and the security-critical secret handling is grouped in its own sentence. The nine-item event enumeration is somewhat redundant with the schema enum, but the rest is dense and 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?

No output schema exists, so the description carrying the secret-return contract and signature format is close to sufficient. Gaps: what happens when events is omitted (subscribe-all vs none), whether an existing URL/event set is replaced, and any default for rotate_secret.

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 only 25% (only rotate_secret documented), so the description does the compensating work: it constrains url to HTTPS, enumerates the event types that events subscribes to, and reinforces rotate_secret's replace-and-invalidate semantics. Worker_id and the default behavior when events is omitted remain unexplained.

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?

States a precise verb+resource ('Point one of your workers at an HTTPS URL') and immediately explains the effect: Tango POSTs signed JSON events to it. It is clearly distinguishable from the sibling read/clear webhook tools and from rotate_webhook_secret.

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?

Gives the motivating condition ('so your agent doesn't have to poll') and routes rotation explicitly to rotate_secret: true or the rotate_webhook_secret sibling. It does not spell out when-not-to-use (e.g. existing webhook replacement behavior), but the alternative path for the one risky sub-operation is named.

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