Add multiple members to a Scaleway IAM Group

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

Annotations already indicate mutation (readOnlyHint=false) and no destructiveness (destructiveHint=false). The description adds value by clarifying the additive nature ('preserved') and the refusal condition for managed groups. It could further disclose behavior when adding already present members (e.g., silent no-op or error) but provides solid context beyond 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?

Two concise sentences: the first states the core purpose, the second adds critical behavioral nuance (additive vs replace, refusal condition). Every sentence earns its place with no redundancy or fluff.

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 moderate-complexity bulk add tool with 3 parameters and no output schema, the description covers the core behavior and an error case. However, it lacks details on what the success response looks like, whether adding duplicate members is safe (idempotent), and partial failure behavior. It is adequate but leaves operational questions unanswered.

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 only 33% (only group_id gets a description in schema). The description does not elaborate on the parameters—it mentions adding 'Users and/or Applications' but does not explain that user_ids and application_ids are arrays of UUIDs, how to acquire them, or that they are optional. With low coverage, the description should compensate but fails to provide meaningful parameter-level guidance.

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 ('Add') and resource ('multiple Users and/or Applications to a Group') and clearly distinguishes from sibling tools like scaleway_iam_add_group_member (singular) and scaleway_iam_set_group_members (replace) by stating 'at once' and 'additive, not a replace.'

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 explicitly states that this tool is additive and not a replace, guiding the agent to use set_group_members for replacement. It also notes that the tool refuses non-editable groups, which informs when not to use it. However, it does not mention the singular variant scaleway_iam_add_group_member as an alternative for adding a single member at a time, leaving some usage gap.

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