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

Annotations already cover the safety profile (not read-only, open-world, non-idempotent, non-destructive), so the description's job is to add context, which it does: it discloses the accepted-terms prerequisite, the required signed message, and the return payload fields. It does not state auth/permission requirements beyond the signature.

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?

A single front-loaded sentence that leads with the precondition and return contents, with the ts clarification appended after a semicolon. No filler.

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?

With 3 required params, no output schema, and no nested objects, the description covers the trigger condition, the signed-message requirement, the ambiguous ts parameter, and the expected return fields. Sufficient for an agent to call it correctly.

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 67% (wallet and signature documented, ts not), and the description compensates by defining ts as 'the epoch ms inside the signed referral message'. This adds genuine meaning over the bare integer type, though the exact message format remains unstated.

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?

States a specific verb and resource ('get the referral code, link, shareText and rules') and even names the backing endpoint (POST /api/referrals/code). It is distinguishable from sibling referral tools by its precondition, though it does not name those siblings directly.

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?

'Use after the terms are accepted' gives an explicit sequencing precondition that tells the agent when this tool is valid, distinguishing it from referral_terms and referral_accept. No exclusion cases or explicit alternative names are provided.

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