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

Annotations already declare this is a non-read-only, idempotent, non-destructive, open-world write. The description adds meaningful context beyond that: the authorization gating and the one-time preview constraint. It does not describe idempotency behavior or what an already-consumed preview yields, which is a modest remaining gap.

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 front-loaded sentences with zero waste; the core action comes first and the conditional usage rule follows. 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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. The description supplies the authorization prerequisites an agent needs before calling. It is essentially complete, minus any note on what happens when the one-time preview has already been consumed.

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 0%, so the description carries the full burden. It conveys the meaning of authorizationMode (AUTOMATIC vs explicit approval) but says nothing about confirmationId, confirmationDigest, or confirmed, whose roles must be inferred from naming. Partial compensation, so a minimum-viable 3.

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 ("Send the exact private message") plus the mechanism ("from a one-time preview"), so it is clearly the confirmation step of the prepare→confirm flow. It does not name the sibling fitmeet_message_prepare explicitly, but the preview reference distinguishes it from chat_confirm and publication_confirm.

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?

Gives explicit when-to-use conditions: AUTOMATIC is permitted only when the prepare result reports standing authorization, otherwise only after the user explicitly approves the named recipient and full text. This maps directly onto the authorizationMode enum and leaves nothing to inference.

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