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

The description adds meaningful behavioral context beyond the read-only and idempotent annotations: institutional scope is longer and assumes more, as_of returns a past edition, and this tool is cheaper than the full brief. It also correctly implies a safe read operation with no destructive side effects.

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?

Four short sentences cover purpose, parameters, behavior, and alternatives without waste. The key purpose is front-loaded, and every sentence adds value.

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 output schema exists and annotations cover safety, the description supplies everything needed to call the tool correctly: parameter values, defaults, date behavior, and how to find valid areas. There are no significant gaps.

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 0%, so the description must carry parameter meaning, and it does: area is illustrated with examples, scope is given with allowed values and default, and as_of is specified with format and semantics. All three parameters are meaningfully explained.

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: retrieving one coverage area's note in full, with concrete examples like real-assets-shipping and real-assets-aviation. It also differentiates from siblings by framing itself as cheaper and more direct than pulling the whole brief.

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?

It explicitly explains when to use this tool versus alternatives: use it to read one theme instead of the whole brief, and call list_coverage to discover the areas and their dates. This gives the agent clear routing guidance.

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