cigchat_subscriber_chat_messages_by_mids

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

With no annotations, the description carries the full burden of behavioral disclosure. It reveals important traits: the limit of 100 mids, the meaning of the type field (in/out/agent), the HTTP endpoint, and the required OAuth scope. It does not describe return format or error behavior, but the 'type' explanation and auth note add valuable context beyond the schema.

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 dense sentence that front-loads the primary action and then adds limit, type semantics, endpoint, and auth requirements. It is concise and each piece of information is relevant. Minor typo ('Ougoing') and lack of structured formatting prevent a 5, but overall it is compact and readable.

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 tool with one parameter and no output schema, the description covers the essential aspects: what it returns (chat messages), the input constraint (mids up to 100), the message type taxonomy, the endpoint, and authorization. It does not describe the response structure or pagination, but for selecting and invoking the tool, this is largely sufficient. A more detailed return description would push it higher.

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?

The only parameter, mids, has full schema coverage with a description and example. The tool description repeats the 'up to 100 mids' limit but does not explain what a mid is or add formatting details. Since the schema already documents the parameter, the description adds marginal value beyond the schema, so baseline 3 is appropriate.

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 tool's purpose: 'Get chat messages by multiple mids, up to 100 mids.' It identifies the specific resource (chat messages), the key qualifier (by multiple mids), and a limit. This distinguishes it from the sibling tool cigchat_subscriber_chat_messages, which likely fetches messages by subscriber rather than by mids.

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 provides clear context for when to use the tool: when you have a list of mids (message IDs) and need their content. It also includes prerequisite access requirements (Manage Flow scope). However, it does not explicitly mention alternative tools or when not to use it, 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.