List webhook subscriptions

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

Annotations only declare readOnlyHint and openWorldHint; the description adds the critical behavioral fact that the gateway rejects the endpoint with a 401 OperationNotFound and that the call surfaces an 'endpoint unavailable' error. It also specifies the intended return shape { id, eventType, callbackUrl, createdAt }, which is far beyond 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?

Three sentences that each carry distinct information: the failure, the intended return shape, and the rationale for keeping the tool. The structure is front-loaded with the unavailability. Slight redundancy between the first sentence's error description and the parenthetical, but no padding.

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 zero-parameter, read-only tool with no output schema, the description covers everything an agent needs: current failure mode, expected error behavior, and the intended return payload. Nothing actionable 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?

The schema has zero properties, so the baseline is 4; there is nothing for the description to disambiguate. It does not add parameter detail, but none is needed.

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 the exact resource (active webhook subscriptions at /v2/subscriptions) and what it would return, and no sibling tool covers subscriptions, so it is trivially distinguishable. It also front-loads that the endpoint is currently unavailable, which is the single most important fact about this 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?

Explicitly tells the agent the call will fail with an 'endpoint unavailable' error rather than returning data, which is effectively a strong 'do not use' signal, and explains the tool is retained for future restoration. It stops short of naming an alternative for listing subscriptions, but no sibling offers that capability.

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