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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses that the returned api_key is the only copy, that signups and wrong codes are rate-limited per address per hour, and that the call requires no prior key. It also explains error behavior (403 access_code_required, 403 invalid_access_code). This is exemplary transparency for a tool with no annotations.

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 dense but well-organized, front-loading the core purpose and then covering prerequisites, error handling, and next steps. Every sentence adds value. It could be slightly more structured (e.g., separating the 'keep the api_key' instruction into its own paragraph), but it's appropriately sized for the complexity of the tool.

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?

The description is complete for an account creation tool. It covers the purpose, required input, error cases, output handling (api_key), rate limits, and next steps. The output schema exists, so return values don't need to be described in detail. The only thing not covered is the exact response format, but that's provided by the output schema. This is a model description.

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 compensate. It explains the access_code parameter in detail (format HD-XXXX-XXXX, case/dashes don't matter, error codes) and the label parameter (optional note up to 120 characters). The only minor gap is that it doesn't explicitly state that both parameters are optional (schema shows default null), but the description implies access_code is needed and label is optional, which is sufficient.

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's purpose: 'Create an account and get an API key with free credits.' It uses a specific verb and resource, and distinguishes itself from sibling tools like request_access and create_access_code by explaining that this is the account creation endpoint, not an access code request. The mention of 'No key needed for this call' further differentiates it from other tools that require an API key.

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 provides explicit when-to-use guidance: it requires a beta access code, explains how to obtain one (request_access or hookdetector.com/access), and states the error codes for missing/invalid codes. It also tells the user what to do next (find_hooks) and how to use the returned key in subsequent calls. This is comprehensive usage guidance.

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