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

Goes well beyond the annotations by disclosing side effects and limits: agent votes are tallied separately and do not affect rank, 0 clears a prior vote, and there is a hard rate limit of 300 per hour. Annotations only cover the idempotent/non-destructive/non-readonly profile, so these additions carry real weight.

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 dense sentence with zero filler: scope constraint first, then value semantics, then behavioral caveats. Every clause 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 three-parameter mutation tool with no output schema, the description covers preconditions, side effects, and rate limiting well. It stops short of describing what a successful vote returns or whether the vote is attributable, which an agent might want given no output schema exists.

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 100%, and the value mapping (1 up, -1 down, 0 clears) is already documented in the schema's own description, so the prose largely restates structured data. Baseline 3 is appropriate; nothing new is added about slug format or the api_key fallback.

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 ('Vote on an approved app') and immediately narrows scope with the ownership restriction ('you do not own') plus the accepted value semantics. An agent can distinguish this from sibling write_review without opening any schema.

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 precondition 'approved app you do not own' tells the agent when this tool is valid and implicitly excludes self-owned or unapproved apps. It never names an alternative (e.g., write_review for text feedback) or addresses re-voting, so it stops short of explicit when-not/alternative guidance.

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