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

The description goes far beyond annotations (which only indicate non-readonly, non-open-world, non-destructive) by disclosing: the one-time signing secret must be surfaced and stored immediately, default events, the full event set including wildcard acceptance, and rejected private/loopback hosts. It warns that localhost tunnels won't work, adding critical behavioral 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 paragraph covering all key points but could be slightly more structured (e.g., bullet points for events). It is front-loaded with the core purpose and usage guidance. Every sentence adds value, but the event list is a bit verbose inline.

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 the tool has 3 parameters, no output schema, and annotations only cover nondestructive/non-readonly flags, the description completely covers usage context, event semantics, secret handling, and URL constraints. The agent has all information needed to invoke it correctly without additional help.

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?

With 100% schema description coverage, the schema already documents all three parameters well. The description adds value by explaining the one-time signing secret behavior (not in the schema) and clarifying that the event set is open-ended ('any other string is accepted'). However, it doesn't describe the enabled parameter's purpose beyond what the schema says, keeping the score slightly below 5.

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 clearly states the tool registers an HTTPS endpoint for Kamy to POST to when work finishes, distinguishing it from polling-based alternatives like get_job or list_renders. The verb 'register' and resource 'HTTPS endpoint' are specific, and the sibling context reinforces the differentiation.

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 explicitly says 'Use this when the caller owns a server that can receive callbacks; use get_job or list_renders when it cannot,' providing clear when-to-use and when-not-to-use guidance with named alternatives. This directly helps the agent decide among siblings.

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