join_group

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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds nothing beyond purpose: it does not mention auth/account requirements, whether the join may require admin approval, or what happens on failure, so it contributes no behavioral context the annotations lack.

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?

A single front-loaded sentence with no filler. It is efficient, though its brevity comes at the cost of the missing usage and behavioral detail scored above.

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?

An output schema exists, so return values need not be explained, and annotations carry the safety profile. However, for a write/mutation tool the description omits account selection, approval-request behavior, and when to prefer preview_group_link, leaving clear gaps.

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 coverage is 50%: the required link parameter is well documented in the schema as a URL or bare code, but the account parameter has no description. The description's mention of the invitation link reinforces the link parameter but adds no syntax or format detail beyond the schema, so it does not compensate for the undocumented account parameter.

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?

States a specific verb (rejoint/joins), resource (un groupe), and mechanism (par son lien d'invitation), so the action is unambiguous. It does not name or distinguish itself from the obvious siblings preview_group_link or group_invite_link, which would make the boundary sharper.

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?

There is no guidance on when to use this versus alternatives such as preview_group_link (which presumably shows the group before joining) or handle_join_requests. The agent gets no exclusions, prerequisites, or context for choosing this tool.

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