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 what the tool returns (ISO positions, comparable grades, verification status per row) and adds an important caveat that comparable-at-ISO-position is only a trial starting point, not an interchangeability guarantee. This is more transparent than typical, though it does not cover all edge behaviors such as unknown grades.

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?

Two sentences with no filler: the first sentence front-loads the purpose and output shape, and the second sentence adds the essential caveat. Every phrase earns its place.

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?

Even without an output schema, the description thoroughly explains what the agent should expect: ISO positions, comparable grades from other manufacturers, and per-row verification status. It also includes a critical usage caveat. For a two-parameter lookup tool, this is fully complete.

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% for both parameters, so the schema already documents 'brand' and 'grade'. The description adds example codes and reiterates that brand disambiguates shared codes, but it does not provide meaning beyond what the schema already contains.

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 specific verb and resource ('Cross-reference a carbide insert grade across manufacturers') and clearly distinguishes it from sibling tools: it deals with carbide grades and ISO 513 positions, while material_cross_reference targets materials and speeds_feeds_starting_values targets starting values.

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 clear context for when to use the tool ('Given any maker's grade... returns its ISO 513 application position(s) and the grades other manufacturers publish'), with examples. However, it does not explicitly name sibling tools or state when to prefer one over the other, so it stops short of full exclusion guidance.

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