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

The 'same vote again = undo' toggle behavior is genuinely valuable context not conveyed by the annotations, and it explains why idempotentHint is false. 'Needs an active key' adds an auth prerequisite. Neither contradicts readOnlyHint=false or destructiveHint=false.

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?

Three terse sentences, front-loaded with the core action, then the undo semantics, then the auth requirement. Nothing is wasted.

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 small mutation tool with no output schema, the description covers the action, the toggle behavior, and the auth prerequisite. Minor gaps remain (rate limits, error behavior) but nothing essential is missing for correct invocation.

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 75%, with enum-like descriptions for direction (up | down) and target_type (post | comment) already in the schema. The description reinforces the target types but adds no detail on the id or api_key parameters. Baseline 3 is appropriate.

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 the specific action (upvote/downvote) and the resource (post or comment), so the agent knows exactly what operation this performs. It doesn't explicitly contrast with the sibling vote_election, but the 'post or comment' scope implicitly separates it.

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?

'Needs an active key' gives a prerequisite, and the target scope implies when to use it. However, there's no explicit guidance on when to prefer vote over vote_election, nor any failure conditions or constraints beyond the auth note.

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