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

With no annotations, the description carries the behavioral burden and does well: it explains that price-book fields are copied as they currently are, that typed-in entry supports optional price and cost, and that any worker can record materials even if they cannot see prices. These are substantive behavioral and permission details beyond the schema, though conflict handling between pricebook_item_id and typed fields is not addressed.

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 front-loaded with the core action and remains compact despite covering two entry modes and permissions. The single long sentence with parentheticals is dense but every clause contributes useful information.

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?

An output schema exists, so return values need not be described. For a 10-parameter mutation tool with no annotations, the description is adequate but leaves meaningful gaps around minor-unit price/cost encoding, precedence when both pricebook_item_id and typed-in fields are provided, and explicit update-vs-add guidance.

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 only 30% across 10 parameters, so the description must compensate. It adds useful meaning for pricebook_item_id, the typed-in fields, job/visit context, and copied price-book attributes, but it does not explain the minor-unit encoding for unit_price_minor/unit_cost_minor or clarify the required quantity parameter beyond what the schema already says.

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: recording a material used on a job, optionally on a visit. It clearly distinguishes the two source modes (price book vs. typed-in), though it does not explicitly name sibling tools such as materials_update or materials_remove.

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?

Usage is implied by 'Record a material used on a job' and by explaining price-book vs. typed-in entry. However, it does not explicitly state when to use this instead of materials_update, materials_remove, or materials_list, nor does it warn about cases where an existing material should be updated instead.

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