kaiten_add_card_member

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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent, open-world mutation, so the safety profile is covered. The description adds one useful behavioral constraint — the user must already exist, so you cannot invite someone by email — but says nothing about what happens if the user is already a member on this non-idempotent tool, nor about required permissions.

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 short sentence with the operation front-loaded and no filler. It is efficient, though the terseness comes partly at the cost of the missing guidance noted elsewhere.

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?

The tool is simple (two required integer params) and an output schema exists, so return values need not be explained. However, for a mutation whose annotations mark it non-idempotent, the description leaves out duplicate-membership behavior and permission requirements, which an agent would need to call it safely.

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 the burden, and it only restates the parameter name ('using user_id') without format, source, or constraints. It never explains how to obtain card_id (e.g., via kaiten_search_cards or kaiten_get_card) or user_id (via kaiten_list_users), and gives no detail on the positive-integer constraint.

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 ('Add an existing user to a card'), which is immediately distinguishable from kaiten_remove_card_member and kaiten_list_card_members. It does not explicitly name those siblings, but the operation is unambiguous.

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 when-to-use guidance and no mention of alternatives such as kaiten_update_card_member_role or kaiten_remove_card_member. The phrase 'an existing user' hints that the user must already be present in the workspace (obtainable via kaiten_list_users), but this prerequisite is never stated as guidance.

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