Simulate webhook

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

Adds real behavioral context beyond readOnlyHint: the payload is signed with the provider's real scheme and the caller's webhook secret, the tool is disabled in live mode, and secrets must not be reused in production. Return shape is sketched ('headers + raw body') rather than fully specified.

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 the tool produces, followed by mode constraints and a safety note. 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?

For a read-only generator with no output schema, the description covers what it emits, the sandbox-only constraint, and the security caveat. The main remaining gap is parameter guidance for the 8 inputs, which the description leaves entirely to the 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 description names no parameters at all despite 8 inputs, 4 required, and only 63% schema coverage. It never explains the relationship between the event type and refund_ref, nor what target_url does (the curl output is documented only in the schema), so it adds no meaning over the schema.

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 product ('Produce a correctly signed webhook (headers + raw body) for local testing'), which cleanly separates it from the verify_webhook sibling that consumes rather than emits a webhook. The scope (signed payload generation) is unambiguous without opening the schema.

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?

Clear context: sandbox mode, local endpoint, replay with curl. It does not name the alternative tool for consuming webhooks (payments_verify_webhook) or state what to do when you need a live endpoint, so exclusions are only partially covered.

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