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

Annotations indicate readOnlyHint=false, and the description aligns by calling it 'Claim', implying mutation. It adds the constraint of one code per agent key and explains the share link and reward, but does not disclose what happens on duplicate claims or any error behavior. The description adds some context beyond annotations but lacks full transparency for a mutating action.

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 with no fluff, front-loading the primary action and then providing the constraint and incentive. It is well-structured and every sentence earns its place.

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?

For a simple one-parameter tool with no output schema, the description covers the purpose, constraint, share link, and reward. It doesn't explain the return value or error scenarios, but for a claim action that's likely acceptable. It also doesn't mention when to use get_my_referrals, but the core usage is clear.

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 already defines the code format (3-24 chars, lowercase, numbers, dashes). The description adds practical guidance by suggesting 'your Moltbook handle works well', which gives the agent a concrete value to use. This goes beyond the schema's format specification.

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 action: 'Claim your vanity referral code', which is a specific verb and resource. It differentiates from siblings like get_my_referrals and get_referral_leaderboard by focusing on the claiming action rather than viewing. The purpose is unambiguous.

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 implies when to use the tool (to claim a code) but does not explicitly mention alternatives or exclusions. It does note 'One vanity code per agent key', which hints at a constraint but doesn't guide the agent on when to use get_my_referrals instead. More explicit routing would improve this.

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