Manage a WhatsApp chat

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

Annotations already signal destructive and non-idempotent behavior, so the description's job is to add context. It adds meaningful behavioral detail: actions happen 'at once, with no draft', pin_message affects 'everyone', clear/delete is scoped to 'the linked account', and user confirmation is required before changes. These are useful traits not captured in structured fields.

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 a single efficient sentence that front-loads the action list and ends with the critical confirmation instruction. There is no filler, though the phrase 'at once, with no draft' is slightly ambiguous and could have been clearer or omitted.

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 multi-action, destructive tool with six parameters and no output schema, the description covers the key invocation context: what actions are available, the account scope, the need for message_id for certain operations, and the confirmation requirement. It does not describe return values or error behavior, but those are less critical given the schema already covers parameter details.

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 high (83%), so the schema already documents chat_id, account_id, message_id, pin_hours, and mute_hours. The description adds some semantic clarification — pin_message applies 'for everyone', star_message operates on a message_id, and clear/delete applies to the linked account — but does not deeply enrich the parameter understanding beyond the schema.

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 a specific verb ('Change a chat') and enumerates the concrete actions it performs (archive, pin, mute, mark_read, etc.), which is far more specific than the title alone. It doesn't explicitly contrast itself with sibling tools like send_message or manage_group, but the action list makes the resource and scope unambiguous.

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?

The description gives clear context for when to use the tool: when a chat-level change is needed (archive, pin, mute, read state, message pin/star, clear/delete, block). It also includes an important process instruction — 'Say what will change and wait for a yes' — which tells the agent how to invoke it safely. It does not explicitly state when not to use it or point to alternatives, so it misses the top score.

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