set_group_membership

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

Annotations already declare the safety profile (readOnly=false, idempotent=true, destructive=false), so the bar is lower. The description nonetheless adds a genuinely useful behavioral fact not in any structured field: groups are auto-created on first use, meaning the call has an implicit upsert side effect on the group itself. It stops short of describing effects on existing members or error behavior.

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?

Two short sentences, zero filler, front-loaded with the primary action before the side-effect note. Every clause 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?

An output schema exists, so return values need not be explained, and annotations cover safety and idempotency. Combined with the description's coverage of add/remove semantics and auto-group creation, an agent has what it needs. Missing only edge-case behavior, such as removing a device that is not a member.

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%, so the description must carry parameter meaning, and it does for the parameter that matters: member=true adds, member=false removes. The device and group parameters are only implied by the sentence structure rather than defined, so it does not fully compensate for the zero coverage.

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 names a specific verb+resource pair ('Add/remove a device to/from a group') and immediately resolves the only ambiguity in the name by mapping member=true to add and member=false to remove. No sibling tool performs group membership mutation (list_groups only reads), so an agent can select it without inspecting schemas.

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 through the boolean semantics: the agent learns which value to pass for adding vs removing. However, there is no explicit when-to-use framing, no prerequisites, and no mention of an alternative path (e.g. list_groups to verify membership first). Adequate but leaves inference on the agent.

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