message_details

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

With no annotations, the description carries the full burden of disclosing behavioral traits. It adds context about returning safe structures and excluding debug secrets, which is helpful, but it does not state whether the operation is read-only, the required permissions, or any side effects. This leaves the agent uncertain about the tool's safety profile.

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, concise sentence that front-loads the core purpose ('Expand one message') and includes only relevant detail ('safe quote/forward/link/file structures without debug secrets'). Every word earns its place, making it highly efficient.

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?

While an output schema is present, the description leaves significant ambiguity around how to specify the message and how the parameters relate. The 0% schema coverage and lack of parameter guidance make it incomplete for an agent to confidently invoke the tool, especially without knowing whether local_id or server_id_str (or both) are required.

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%, and the description provides no explanation of the three parameters (chat, local_id, server_id_str). It does not clarify how to identify a specific message, whether local_id and server_id_str are alternatives, or that chat is required. The description fails to compensate for the schema 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 uses the specific verb 'expand' and clearly identifies the resource as 'one message'. It further distinguishes the tool from siblings by mentioning safe quote/forward/link/file structures, which implies a detailed message view rather than a timeline or media-specific operation.

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?

Usage is implied from the phrase 'one message' – it is for when you need details of a single message. However, there is no explicit guidance on when to use this versus alternatives like timeline or read_chat_range, nor any exclusions or prerequisites. The description lacks a clear 'when to use' statement.

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