scf_create_webhook

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

Annotations only say readOnlyHint=false and destructiveHint=false, so the description carries the burden of explaining the write nature and admin requirement. It adds critical non-obvious behavior: the plaintext HMAC signing secret is returned exactly once, must be stored immediately, and cannot be retrieved later. This is exactly the kind of behavioral disclosure an agent needs.

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?

Two tight sentences: the first defines the action and purpose, the second delivers a one-time secret warning. No filler, no repetition of schema content, and the most important operational caveat is front and center.

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 create operation with a fully documented input schema, the description covers the key non-obvious outcome: the one-time return of the HMAC secret. It does not enumerate the full response shape, but no output schema exists and the critical handling instruction is present. Overall, an agent has enough to invoke the tool correctly and handle the result safely.

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 schema has 100% parameter description coverage, so the description does not need to explain parameters. It does not add much parameter-specific meaning beyond the schema, staying at the baseline for high schema coverage. The mention of HMAC secret is about the response, not the parameters.

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 specific verb and resource: 'Create a webhook endpoint' with a clear purpose ('for evidence-inbox ingestion'). The parenthetical '(write — admin role)' further clarifies the operation type. Among the many webhook-related siblings (list/get/delete/rotate), this stands out as the creation tool.

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 clearly indicates this is for creating a webhook endpoint and flags that it is a write operation requiring admin role. It does not explicitly name alternatives such as scf_list_webhooks or scf_rotate_webhook_secret, but the creation context is unmistakable and sufficient for basic tool selection.

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