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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered; the description adds useful behavioral detail about page sizing and the exact paging cursors returned. It doesn't cover rate limits or auth, but the bar is lower with annotations present.

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 dense sentences with the returned-field list and paging contract front-loaded, no filler. The trailing 'GET /v1/materials/?siteId=.' fragment is an incomplete dangling artifact that adds little since siteId isn't a declared parameter.

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?

With no output schema, the description compensates by naming the response envelope fields (recordCount, next_start_index) an agent needs to page correctly. Only the unimplemented siteId reference and absent filtering guidance keep it from being 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 coverage is 100%, so the baseline is 3, but the description adds response-side semantics by explaining that the reply carries recordCount and next_start_index, which gives the paging parameters meaning the schema alone doesn't convey. It doesn't clarify sort/order or is_archived behavior beyond the schema.

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 ('List materials/ingredients') and enumerates the returned fields (code, supplier code, category, countries of origin, risk, archived flag), which distinguishes it clearly from the sibling get_material/get_final_product single-record tools.

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 pagination contract ('paged with start_index and limit; the reply carries recordCount and next_start_index') implies how to page through results, but there is no explicit statement of when to choose this over get_material or how to filter archived vs active records.

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