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

Annotations already declare readOnlyHint=false, destructiveHint=true, idempotentHint=true, and openWorldHint=true, so the safety profile is covered. The description adds a genuine behavioral trait beyond those: the like is performed 'asynchronously,' implying the effect may not be immediate or confirmed synchronously, plus a platform scope restriction. It does not say what happens on failure or whether the profile must be authorized on the post.

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 with zero filler; the core action is front-loaded and the platform caveat follows immediately. No sentence is redundant with the name, title, or schema.

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 with full schema coverage and annotations carrying the safety profile, the description covers the essentials and adds the async caveat and platform scope. Remaining gaps (authorization requirements for the acting profile, failure behavior) are minor 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%, so post_id, comment_id, and profile_id are already documented with baseline descriptions. The tool description adds no format, ID-namespace, or pairing detail beyond the schema (the comment_id Postproxy-vs-external distinction lives only in the schema), so 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?

The description gives a specific verb and resource ('Like a comment') that an agent can distinguish from comments_create, comments_edit, and the inverse comments_unlike without opening a schema. It stops short of 5 because it does not explicitly name the sibling that removes a like (comments_unlike), leaving that routing to inference.

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?

Usage guidance is limited to the platform constraint 'Currently only supported on Facebook,' which usefully tells the agent when the tool is applicable. There is no explicit when-to-use-vs-alternative statement (e.g., pointing to comments_unlike to undo), so guidance is implied rather than stated.

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