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

With no annotations supplied, the description carries the behavioral burden well: it discloses partial-update semantics ('fields left out stay as they are'), the destructive-ish effect of verify: null ('stops checking signatures'), the reset effect of accept: null, and the side effect of replacing the stored secret. It omits what the call returns and whether name itself is mutable, which leaves some gaps for a mutation tool with zero annotation coverage.

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 short sentences, front-loaded with what changes, then what stays stable, then null/omission semantics, then a caveat about secret rotation. Nothing is repeated from the schema and every sentence carries distinct 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?

For a four-parameter mutation tool with no annotations and no output schema, the description covers the important behavioral surprises: preservation of URL/counts/delivery IDs, omission meaning no change, and null semantics. It could additionally state the response shape or that unknown fields are rejected, but an agent could invoke this correctly as written.

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?

Beyond the schema's own field docs, the description adds real meaning: null values have distinct semantics (accept null removes filtering, verify null disables signature checking), and passing verify silently replaces the stored secret. The required 'name' parameter's role as an immutable identifier is never clarified, which is the main remaining ambiguity.

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 ('Change a hook's verify, accept or keep_headers'), so the agent immediately knows this is a partial mutation of hook configuration rather than creating or deleting one. It does not explicitly name siblings like create_hook or delete_hook, but the mutability set is precise enough that confusion is unlikely.

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 clear usage context: use it when rotating the sender's secret, and it explains that the URL and delivery history stay stable so no sender-side change is needed. It does not state explicit exclusions (e.g. 'to create a hook use create_hook, to change the URL delete and recreate'), so the when-not guidance is only implied.

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