add_party_member

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the action is an 'Add' operation (implying mutation), but doesn't describe what happens on success/failure, whether duplicates are allowed, if position affects ordering, or any permission requirements. The description mentions the role parameter but doesn't explain behavioral differences between roles (e.g., leader privileges).

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?

The description is a single, efficient sentence that front-loads the core purpose. Every word earns its place - 'Add a character to a party' establishes the action, and the parenthetical role details provide necessary parameter context without redundancy. No wasted words or structural issues.

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 mutation tool with 6 parameters (0% schema coverage), no annotations, and no output schema, the description is insufficient. It covers the basic purpose and one parameter's semantics but misses behavioral context, usage guidelines, and documentation for most parameters. The agent would struggle to use this tool correctly without additional context.

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 compensate. It explicitly mentions the 'role' parameter with its enum values, adding semantic meaning beyond the bare schema. However, it doesn't explain the other 5 parameters (partyId, characterId, position, notes, sessionId), leaving them completely undocumented. The partial coverage of one parameter justifies a baseline score.

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 clearly states the action ('Add a character to a party') and specifies the resource ('party') with the role parameter details. It distinguishes this tool from general character management tools like 'create_character' or 'update_character', but doesn't explicitly differentiate it from the sibling tool 'remove_party_member' or other party-related tools like 'update_party_member'.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., party and character must exist), when not to use it (e.g., for updating existing members), or refer to related tools like 'update_party_member' or 'remove_party_member' that handle different party member operations.

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