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

Adds substantial behavior beyond the annotations (which only say readOnly=false, openWorld=true, non-idempotent, non-destructive): payloads are signed, the signing secret is returned exactly once and cannot be retrieved again, and the user must approve the URL. These are exactly the operative facts an agent needs to act safely, and nothing contradicts the annotations.

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?

Three tight sentences, each carrying a distinct piece of load-bearing information (effect, secret handling, approval requirement), with the core action stated first. 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 non-idempotent, open-world mutation tool with no output schema, the description covers the effect, the one-time secret in the response, and the approval prerequisite — everything needed to call it correctly and handle the result.

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 coverage is 100%, so both parameters are already documented with max length and the event enum; baseline would be 3. The description goes beyond that by tying the url parameter to the account-data/approval constraint and framing events as 'the chosen events', adding usage meaning not present in 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+resource ('Register an outbound webhook') and immediately defines the effect: MisarPost will POST signed payloads for the chosen events to this URL going forward. This cleanly separates it from list_webhooks, update_webhook, and delete_webhook without needing to name them.

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 a clear precondition for use — 'Sending account data to a new URL needs the user's explicit approval of that URL' — which is real routing guidance for a mutating tool. It does not name an alternative tool or state when not to use it, so it stops short of a 5.

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