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

Annotations provide only destructiveHint=true and a title. The description adds a genuinely useful behavioral constraint not in the schema: that assignedUserId or assignedTo is required despite the schema listing only personId as required. However, it says nothing about side effects, permissions, or what the call returns, leaving the destructive hint unexplained.

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 compact sentences, front-loaded with the core action and the key constraint. The 'FUB: POST /v1/tasks' endpoint reference is minor but non-redundant. No wasted prose.

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 9-parameter creation tool with no output schema, the description is thin: it omits defaults, side effects, and the meaning of the destructive annotation. The schema and the added assignment rule cover enough to invoke it, but behavioral completeness is only adequate.

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 coverage is 78% (high), so the schema already documents most parameters. The description adds the either/or assignment semantics for assignedUserId/assignedTo, which is real value beyond the schema, but nothing else about the remaining params.

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 ('Create a task on a contact') and clarifies the assignment requirement. Distinguishable from siblings like fub_update_task and fub_list_tasks, though it doesn't explicitly name them.

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?

No when-to-use vs alternatives guidance; it doesn't say when to prefer this over fub_update_task or how it relates to notes/events. The only context is the assignment requirement, which is a constraint rather than usage guidance.

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