discord_get_thread_member

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

Beyond the annotations' read-only/idempotent profile, it discloses the 404 failure mode and the absence of required bot permissions, which are real behavioral facts an agent cannot infer from structured fields. It does partly repeat the annotations ('Read-only; safe to retry'), and it says nothing about rate limits or response shape, so it falls just short of the top score.

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?

Four short sentences, zero filler, and the core purpose is front-loaded ahead of the failure mode, the option flag, and the sibling routing. Each sentence carries distinct information except the redundant safety clause.

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 an output schema present, the description need not explain return values, and it still covers purpose, the one behavioral option, the error case, permission requirements, and the sibling alternative. Nothing an agent needs in order to invoke this correctly is missing.

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%, so all three parameters are already documented. The description's note about with_member ('include full guild member details') largely restates the schema wording, and it adds no format or constraint detail for channel_id/user_id beyond the pattern already given. Baseline 3 applies.

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 gives a specific verb and resource: 'Fetch membership details for one user in a thread', and it names what the result contains (join timestamp and flags). It also contrasts with a sibling (list-all vs. single-user), so the agent can choose between discord_get_thread_member and discord_list_thread_members without opening either schema.

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?

It explicitly routes to the alternative: 'To list all members of a thread, use discord_list_thread_members.' It also makes clear when the call should fail (404 if the user is not a member) and how to widen the payload (with_member=true), which is exactly the selection guidance an agent needs.

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