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

Annotations provide idempotentHint=true, destructiveHint=false, readOnlyHint=false, but the description adds zero behavioral context. It does not disclose side effects, idempotency semantics, required permissions, or any operational traits. Since the description's role is to add value beyond annotations, and it adds none, this scores minimal.

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 vague sentence, which is short but not concise in a helpful way. It is under-specified rather than efficiently packed with information. It does not front-load any actionable guidance, making it more of a placeholder than a structured definition.

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?

Given the tool's complexity (nested objects, required parameters, no output schema), the description is completely inadequate. It does not explain return values, error conditions, or the purpose of the payload structure. An agent would have no idea what to expect or how to interpret the schema.

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 for the lack of parameter documentation. However, the description does not mention any parameters, their meaning, or relationships. The schema shows required fields (projectId, idempotencyKey) and optional ones, but the description offers no explanation, leaving agents to infer everything from schemas alone.

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 'Use the closed activity write capability family from the frozen Brain Scanner policy' is extremely vague. It does not state what the tool does, what operation it performs, or what resource it affects. It fails to distinguish from siblings like record_activity, context_write, or knowledge_write, all of which are write operations. It is more of an opaque reference than a purpose statement.

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 guidance on when to use this tool versus alternatives. The description does not mention any conditions, exclusions, or alternative tools. An agent cannot determine when this is the appropriate choice among the many write tools in the sibling list.

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