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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds meaningful context: no auth required, the free-trial meter limits, cache applies only to input tokens, and the conversion to prepaid ACH human retainers with specific prices and durations. This goes beyond the structured fields.

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 compact and front-loaded: it opens with the tool's purpose, then adds constraints and model details. It packs a lot of useful information without excess verbosity, though the retainer conversion sentence is dense and could be slightly clearer.

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 read-only quote tool with no output schema, the description covers the request shape, input constraints, authentication requirements, and usage limits. The only minor gap is that it does not describe what the response looks like (e.g., currency, format), but the read-only annotation and the quote purpose make that less critical.

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?

The schema already has 100% description coverage, so the baseline is 3. The description adds value by specifying the POST JSON field names ('agents, callsPerAgentPerDay, inputTokensPerCall, outputTokensPerCall, cachePct, days, model') and clarifying that cache applies to input tokens only, which complements the schema's cachePct description. It also mentions the conversion to retainers, giving extra context about how the quote is used, though it does not detail every parameter's formatting.

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 a specific verb ('Return a list-price spend quote'), the resource ('a fleet of agents'), and the method (POST JSON). It distinguishes itself from generic pricing endpoints by specifying the input shape and the list-price nature.

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 explicitly says 'No auth' and describes the free-trial / stress-test meter limits (100 calls or 14 days), which tells the agent when it is appropriate to use the tool and what constraints apply. It does not mention alternative sibling tools because there are none, so no exclusion guidance is needed.

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