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

With annotations already covering safety (readOnlyHint=false, idempotentHint=true, destructiveHint=false), the description adds real behavioral context: unsupported platforms return comment_action_unsupported instead of a false success, and a hidden comment remains in the Chirpie listing behind include_hidden so moderation history is preserved. That is exactly the extra layer annotations cannot express.

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 tight sentences, no filler, and the core capability is front-loaded ahead of the platform caveat and the persistence note. Every sentence carries distinct information.

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 no output schema, the description covers the operation, platform support, failure token and post-hide state, so an agent has what it needs. Minor gap: it does not state reversal/permission requirements beyond what the idempotent annotation implies.

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 every parameter (hidden, post_id, comment_id) is already documented in the schema, so the baseline is 3. The description adds no syntax or format detail beyond what the schema provides; include_hidden refers to a listing tool, not this tool's inputs.

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 (hide/unhide a comment) plus a scope constraint ('on a post you published'), which cleanly distinguishes it from chirpie_delete_comment and chirpie_hide_post. An agent can route to it without opening the 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?

Explicitly scopes availability (Facebook, Instagram and Threads support hiding) and tells the agent what happens elsewhere, which is strong when-to-use guidance. It stops short of naming sibling alternatives such as chirpie_delete_comment for outright removal, so it is not a full when/when-not treatment.

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