get_messenger_chat

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

No annotations are provided, so the description carries the full burden. It only says 'Get full details' and provides no behavioral context such as read-only nature, authentication requirements, rate limits, or error handling. The presence of an output schema covers return values, but the description adds minimal behavioral disclosure beyond what the tool name implies.

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 short and well-structured: a one-sentence purpose followed by a single parameter definition. It is front-loaded with the key information, contains no filler, and every sentence 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?

For a low-complexity tool with an output schema, the description covers the essential purpose, parameter, and source relationship. It lacks explicit guidance on when not to use it or comparison to alternatives, but the reference to list_messenger_chats partially fills that gap. Overall, it is sufficiently complete for selection and invocation.

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 schema has zero description coverage, and the description fully compensates. It explains that 'name' is the Messenger activity ID, provides an example format ('ACT00123'), and tells the agent how to source it from 'list_messenger_chats'. This is rich, actionable semantic information 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 uses a specific verb and resource: 'Get full details of a single Facebook Messenger activity by its ID.' It clearly identifies the action (get), the resource (Facebook Messenger activity), and the scope (single, by ID). This distinguishes it from sibling get_*_chat tools by specifying the channel.

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 implies usage: obtain an ID from 'list_messenger_chats' and then call this tool to get full details. The example and reference to the list function provide clear contextual guidance on when to use this tool, though it does not explicitly state exclusions or alternatives.

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