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 the returned field set and the underlying GET endpoint, but says nothing about pagination behavior, response size caps, or auth requirements beyond what the schema already implies.

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 short sentences, front-loaded with the resource and returned fields. The trailing "GET /suppliers." is mildly redundant for an agent but does hint at the REST shape, so it is not wasted enough to drop below a 4.

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 usefully enumerates what comes back (contact details, company, account number, balance), and all six params are fully documented in the schema. It is close to complete for a filtered-list tool; only paging semantics and any supplier-specific filters are unaddressed.

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% with enums for sort_dir and search_field, so the schema carries the parameter burden. The description adds no extra meaning such as search matching semantics or how search interacts with search_field, so the baseline of 3 applies.

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 (list/search) and resource (suppliers) plus the fields returned, so an agent can tell it is a collection read. It does not explicitly contrast with phppos_get_supplier for the single-record case, leaving that differentiation to be inferred from the name.

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?

"List or search" implies the two usage modes, and the search/sort parameters support them, but there is no explicit when-to-use guidance or naming of alternatives such as phppos_get_supplier. Usage is implied rather than stated.

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