assign_card

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

With no annotations, the description carries the full burden and does reasonably well: it discloses that assignment is additive ('adds to existing assignees without duplicates') and documents the 'agent:<identifier>' convention for column agents. It does not mention required permissions, what happens if the board/card does not exist, or the response, so it is not fully transparent.

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?

Three short sentences, front-loaded with the core action, then behavior, then the agent-format detail. No filler; every sentence carries information.

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 simple three-parameter mutation with no output schema, the description covers the action, the additive/dedup behavior, and the agent identifier convention, which is most of what an agent needs. Missing elements are permission requirements and failure behavior, minor for a tool of this complexity.

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 the schema already documents cardId, boardId, and assignee. The description's mention of 'agent:<identifier>' mirrors the schema's assignee description, adding no new semantics beyond the structured field. 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?

States a specific verb+resource: 'Assign a user or agent to a card.' An agent can immediately distinguish this from unassign_card or update_card. It does not explicitly name the sibling it contrasts with, so it stops short of a 5.

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 only implied by the verb; there is no statement of when to use this versus unassign_card or update_card, no prerequisites, and no exclusions. The additive note hints at context but is behavioral, not routing guidance.

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