meta_subscribe_webhook

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

Annotations indicate idempotentHint=true and destructiveHint=false, which align with a subscription creation that is safe to repeat. The description adds the credential requirement but does not elaborate on side effects, success/failure conditions, or any rate limiting. With annotations present, the bar is lower, and the description provides minimal additional context.

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?

The description is a single sentence of 14 words, front-loading the core action and including the crucial credential requirement. No extraneous information.

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?

Given 4 required parameters, full schema coverage, and no output schema, the description is minimal. It states the purpose and credentials but omits details on error responses, verification process, or any constraints beyond credentials. However, the annotations (idempotentHint, openWorldHint) reduce the need for extensive behavioral description, making it moderately complete.

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 the baseline is 3. The description does not add any extra meaning to parameters beyond their names and schema descriptions; for example, it does not explain the format of 'fields' or 'callback_url' constraints. The value added is neutral.

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?

The description uses a specific verb 'Subscribe' and identifies the resource as 'webhook notifications for an object' with examples ('instagram', 'page'). It clearly distinguishes from sibling tools which are mostly about data retrieval or publishing operations, not webhook management.

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 mentions the prerequisite 'Requires META_APP_ID and META_APP_SECRET', but does not explicitly state when to use this tool versus alternatives such as meta_get_webhook_subscriptions (for listing existing subscriptions). The guidance is implicit rather than explicit.

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