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

With no annotations, the description carries the full burden and does so: destructive and irreversible, deliveries stop immediately, the signing secret is discarded, cross-key deletes return {"deleted": false} and change nothing, and a Pro/Bot key is required. This far exceeds what annotations would typically cover.

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?

Dense and front-loaded: the destructive warning and ownership rule precede the parameter and auth notes. Every sentence adds a distinct fact (reversibility, side effects, error case, auth tier) with 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 destructive mutation tool with no annotations and no output schema, the description supplies everything needed: irreversibility, side effects, auth requirements, id provenance, and the failure return shape. Nothing an agent needs to call it safely is missing.

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 0%, so the description must compensate, and it documents both params: id is 'the number returned by create_alert or list_alerts' and api_key is explained as the X-API-Key header of the MCP connection or the api_key field. No parameter is left ambiguous.

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 (permanently delete one webhook alert subscription) with explicit singular scope. It distinguishes itself from create_alert and list_alerts, which it names directly, so an agent can route to it without opening another 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 is given: it deletes a subscription and points to create_alert as the way to re-obtain a signing secret. The ownership constraint ('only a subscription owned by the caller's API key can be deleted') is a strong use condition, though it stops short of an explicit 'use X instead when' exclusion.

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