create_webhook

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

With no annotations provided, the description carries the full burden and does so excellently. It discloses the one-time HMAC signing secret that must be saved and won't be shown again, plus the 402 error on free-tier. This is critical behavioral context beyond the schema and enriches the agent's understanding of side effects and prerequisites.

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 moderately long, but every sentence carries unique value: purpose, required params, optional params, return details, and error/plan restriction. It is well-structured and information-dense without being verbose.

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?

Despite having an output schema, the description adds extra context the schema wouldn't provide: the one-time secret caveat, the HTTPS requirement, and the paid-plan error condition. It covers the full lifecycle of the call—inputs, outputs, and failure modes—making it highly 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 description coverage is 0%, so the description must explain all parameters. It does this thoroughly: url must be HTTPS, events uses examples like 'filing.created', filing_types narrows to form types like '10-K'/'8-K', and description is for user notes. This fully compensates for the empty 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?

The description opens with a clear verb-resource pair: 'Create a webhook subscription.' It explicitly lists required and optional parameters, and the sibling tools (update_webhook, delete_webhook, list_webhooks) make it unambiguous that this is a creation tool. No ambiguity.

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 gives clear context: required HTTPS URL and events, optional filing_types and description, and a note that webhooks require a paid plan. It doesn't explicitly call out when not to use it or reference alternatives, but the sibling tool names imply the distinctions. This is clear enough for an agent to select this tool for creation.

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