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

With no annotations, the description carries the full burden of behavioral disclosure. It explicitly states that the tool never sees an unblinded pass, highlighting a privacy guarantee. It also describes the token blinding requirement and the output (blind signatures). While it does not mention error handling or side effects beyond the daily limit, it provides essential behavioral context (e.g., process steps, privacy) that an agent needs.

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 three sentences long, each serving a purpose: stating the action and outcome, specifying the daily limit, and explaining the unblinding process and privacy feature. It is front-loaded with the core function and contains no redundant or filler text, making it highly concise.

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 tool is simple (one parameter, no output schema) and the description covers input format, constraints (daily limit), process (blinding, signing, unblinding), and a privacy guarantee. However, it omits potential error scenarios (e.g., exceeding daily limit, invalid token format) and the exact return structure (though signatures are implied). Given the low complexity and helpful detail, it is nearly 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?

The schema provides no description for the single 'blinded' parameter (0% coverage), so the description must compensate. It does so effectively by specifying the parameter is an array of up to 20 base64-encoded blinded tokens from the plus-sdk 'blindTokens()' function. This gives the agent precise format and source information beyond the schema's basic type and constraints.

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 function: submit up to 20 blinded tokens to receive blind signatures for trial passes. It specifies the exact resource (blinded tokens) and action (submit/receive signatures), and distinguishes itself from siblings like robyn_plus_claim by emphasizing the trial nature and the blinding process. The phrasing 'identical unlinkable passes to paid ones' further clarifies its purpose.

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 clear context for when to use this tool: for trying Plus before paying, with a constraint of 'one trial per day per caller.' It also mentions the SDK method for unblinding, which implies the workflow. However, it does not explicitly state when not to use this tool or compare it to alternatives like robyn_plus_claim, lacking explicit exclusions.

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