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

Beyond the annotations (readOnlyHint=false, destructiveHint=true), the description extensively discloses behavioral traits: rotate invalidates the old URL immediately without redeploy, set_signing_secret returns a minted secret only once and never echoes stored secrets, clear_signing_secret removes the signing secret, and signature verification currently 'ships dark' (nothing verifies a signature). This provides substantial context that annotations alone do not cover, with no contradictions.

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 longer than average but well-structured: it opens with a definition, then explains the manifest/deploy constraint, and then breaks down each action. Every sentence contributes meaningful context (e.g., external system examples, behavior on rotate, dark signature). Some redundancy with the schema's action descriptions exists, but it does not feel bloated for the tool's multi-action complexity.

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?

Given the tool's complexity (5 parameters, 4 actions, no output schema), the description is remarkably complete. It explains what each action returns (URL once, secret once), the lifecycle (no create/delete, secrets not echoed), and the current limitation of signature verification. It covers edge behaviors (old URL stops immediately, grace_seconds for rotation) sufficiently for an agent to invoke it correctly without an output schema.

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 input schema already covers all parameters with high detail (100% coverage), so baseline is 3. However, the description adds clarifying context about the difference between URL secret and signing secret, and explains the 'secret' parameter's two paths (omit to mint vs pass to store verbatim), which enhances understanding beyond the schema. It doesn't introduce new parameter syntax but improves semantic comprehension.

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 explicitly states the tool manages a v2 app's inbound catch-hooks, with a clear resource (inbound-webhooks) and specific actions (list, rotate, set_signing_secret, clear_signing_secret). It distinguishes from siblings by focusing on webhook URL management and signing secrets, and clarifies it has no create/delete. This is a specific verb+resource that is unambiguous.

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 explicit usage context: 'After deploying a manifest that declares a hook, list is what yields the exact URL to paste into the external system.' It also states when not to use the tool ('no create or delete') because hooks are declared in the manifest and materialized at deploy. This provides clear when/when-not guidance, and while no alternative sibling is named, the exclusion is sufficient for this unique tool.

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