Send read receipts

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

Annotations already cover idempotency and non-destructiveness, so the description only needs to add context. It adds the default behavior ('every unread inbound message wuapi stores'), the blue-tick effect, and the inbound-message constraint, which go beyond the schema and annotations.

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?

One concise, front-loaded sentence with no filler. It communicates purpose, scope, and default behavior efficiently, and 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?

The description, combined with the complete parameter schema and annotations, provides enough information for an agent to invoke the tool correctly. It does not describe return values, but no output schema exists and the lack of return-value detail is not critical here.

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 100%, so the baseline is 3. The description adds value by explaining that messageIds is optional and defaults to every unread inbound message, clarifying the relationship between the parameter and the tool's behavior beyond the schema text.

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 read receipts (blue ticks) for inbound messages in a chat. It clearly distinguishes from sibling mark_chat_read by focusing on receipts rather than chat read state, and the 'given ids or every unread' scope makes the behavior unmistakable.

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: use when you want to send blue ticks for inbound messages, optionally for specific ids or for all unread ones. It does not explicitly name alternatives or exclusions, so it misses the top score, but the intended use case is evident.

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