List 3D printers, materials and pricing

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

With no annotations provided, the description carries the full burden. It discloses that the tool is 'FREE' and 'No payment required', returns 'live' data, and specifies exactly what is included. While it does not explicitly state 'read-only', the verb 'returns' implies a safe discovery operation, and the cost/liveness context adds transparency beyond the 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 two sentences, front-loaded with 'FREE' and 'Discovery', and every clause adds specific detail about the returned data. There is no filler or repetition.

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?

The description thoroughly details the return payload (12 printers with fields, 12 materials, pricing tiers), explains the 'call first' purpose, and notes cost. Even without an output schema, the description fully compensates by enumerating the exact items and their purpose.

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 input schema is empty, so the baseline is 4. The description adds value by explaining that the tool outputs printer and material IDs specifically for use in other tools, which gives the agent context for parameter selection in subsequent calls, even though this tool itself has no parameters.

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 tool's function: it lists the 3D printer fleet, materials, and pricing tiers. It uses the specific verb 'returns' and names the resources, and distinguishes itself from siblings by positioning this as the initial discovery step before quoting, slicing, or DFM checks.

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 instructs to 'Call this FIRST' to choose printer and material IDs before using quoting, slicing, or DFM check tools. This provides clear when-to-use guidance and differentiates it from downstream sibling tools.

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