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

The annotations declare this is not read-only and not destructive, but nothing in them conveys toggling. The description's disclosure that a second call removes the like is a genuinely important behavioral trait (idempotency-by-reversal) that the agent cannot get from structured fields, and it prevents an agent from double-liking by accident.

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?

Two short sentences, zero filler, with the action stated first and the side effect second. 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 simple toggle with no output schema and full parameter coverage, the action, target, and reversal semantics are all covered. A minor gap remains: given the tool name 'react_to_post', the description never confirms that 'like' is the only reaction type supported, and it does not mention auth requirements that the schema handles only implicitly.

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%, so both 'id' and 'api_key' are already documented in the schema. The description adds no additional meaning about the id format or the auth fallback, so the baseline 3 applies.

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 ('Like a feed post') and immediately clarifies that the resource is a feed post, which separates it from comment_on_post and create_post. It does not explicitly name a sibling alternative, but the intent is unmistakable.

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?

'Calling it again removes the like' gives real usage guidance about repeat invocation, which is the most important thing an agent needs to know for this tool. However, it says nothing about when to like versus comment on or reply to a post, and no exclusions or prerequisites are given.

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