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

The description significantly exceeds the annotations by disclosing side effects (automations paused for 30 minutes), special behavior on mention threads (public reply), refusal behavior (window_closed), and the draft-approval flow. This gives an agent a clear picture of what actually happens when the tool is called.

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?

The description is compact, front-loads the primary action and the most critical constraint (24-hour window), then covers secondary behaviors in separate sentences. There is no filler, and every sentence contributes actionable 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?

Given the absence of an output schema and the tool's mutating nature, the description covers the key behavioral context: when it succeeds, when it fails, side effects, and draft usage. It does not describe the success response shape, but the critical error case is named, making it sufficiently complete for an agent to call this tool correctly.

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 80%, so the schema itself documents most parameters. The description adds useful context for draftId ('AI draft that was waiting for approval') but does not explain text, mediaId, or workspaceId beyond the schema. It meets the baseline but does not substantially compensate for the 20% gap.

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 clearly states the action ('send a message in a conversation as the account') and specifies important scope details like the 24-hour window and mention-thread behavior. It does not explicitly distinguish this from sibling tools like reply or create_comment_to_dm, so it misses the last bit of differentiation.

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?

It gives explicit usage conditions: only inside the 24-hour window, otherwise the call is refused with window_closed, and draftId is for sending AI drafts awaiting approval. It does not name alternative tools or say when to choose those over this one, but the window constraint strongly shapes when this is appropriate.

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