Open a Facebook Group

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

Goes beyond the readOnlyHint annotation by explicitly stating it will not join the group, describing behavior for private groups (returns metadata and no posts) and clarifying that this is reported explicitly rather than as an error. This adds valuable behavioral context not in the 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?

The description is three sentences, front-loaded with the primary action, and every sentence adds meaningful information (behavior, return data, edge cases). No wasted words.

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?

With no output schema, the description adequately explains the return value (group metadata plus posts with URL, author, text, timestamp). It also covers an important edge case (private groups). It does not detail every metadata field, but the coverage is sufficient given the schema describes parameters and the description handles the key behavioral context.

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 100% with each parameter having a detailed description. The main description adds little beyond the schema, only mentioning 'newest first by default' which aligns with the sort parameter's default. This meets the baseline for high schema coverage but does not add substantial extra value.

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 action ('open a group and read its visible posts'), the resource (Facebook group), and the scope (visible posts, newest first). It distinguishes from sibling tools like search_groups or open_page by focusing on reading posts from a known group and explicitly describing the return data.

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: use this to open a group and read posts, noting the default sort order and private-group behavior. It does not explicitly name alternatives or when-not-to-use scenarios, but the context is sufficiently clear for an agent to infer appropriate use.

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