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

Beyond the read-only and idempotent annotations, the description discloses that the tool is free, requires no key, makes no network call, and never resolves or invents a value. It also explains the as_of omission behavior, the RETRIEVED fallback, and the per-layer licensing nuance, which annotations cannot convey.

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 densely packed and front-loaded with the usage trigger; the licensing explanation, omission behavior, and anti-lookup warning each earn their place. The long run-on sentences and repeated emphasis could be tightened, but there is no meaningful filler.

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 five-parameter, no-required tool with an output schema, the description covers invocation, return field names, edge cases such as missing as_of and dropped URLs, and disambiguation from the many retrieval siblings. An agent has enough information to call it correctly without needing 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 100%, so the baseline is 3 even though the description restates all five parameters at a high level. It adds the workflow principle 'pass what you read off the response' and notes that layer decides the licence, but it does not add new syntax, formats, or enum semantics beyond the schema.

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 states a precise verb and resource: it returns one paste-ready attribution line for a value about to be quoted, with the layer-correct licence. It clearly distinguishes itself from data-retrieval siblings by saying it cites a figure you already have rather than looking one up.

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 gives an explicit trigger: 'Use right before you QUOTE a DC Hub figure to a human.' It also gives an explicit exclusion: 'Do NOT use to look a figure UP (call the data tool first); this cites a figure you already have.' This tells the agent exactly when to invoke it and what to do instead.

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