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

With no annotations, the description carries the full burden and does so: rate limit of 10 per hour per IP, a precise 501 pipeline_execution_unavailable failure mode and its flag condition, no-credential operation, and partial-failure semantics (unrunnable stages go to not_run while the rest still prices). These are exactly the behaviors an agent cannot infer elsewhere.

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?

Six short sentences, front-loaded with what it does, then constraints, then failure/partial-result behavior. No filler and no restatement of the title.

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 nested-object tool with no output schema, the description covers auth, rate limits, error mode, and partial results well. It leaves the shape of the returned pricing answer unspecified, which for a computed-pricing tool would have been useful to sketch.

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. The description reinforces the context precondition (current_price or unit_cost) and implies image_consent matters only for image-reading pipelines, but adds little beyond the schema's own descriptions and says nothing about selecting among the seven pipeline enum values.

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 and resource: run one of seven named reference pipelines on the pricing-chain engine, with computed (not retrieved) numbers. It is clearly not a listing or single-price tool, though it never explicitly contrasts itself with the keyed sibling run_pricing_chain or compute_price.

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?

"Without a key" / "works without a Last Price credential" gives a clear condition for choosing this over credential-gated pricing tools, and it routes the agent to list_pricing_pipelines for discovery. It stops short of naming an explicit alternative or a when-not-to-use condition.

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