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

With readOnlyHint=true already covering the safety profile, the description adds genuinely new facts: it is free (a cost signal not in annotations) and it returns both ID-bearing filter options and a pasteable snippet. It does not discuss rate limits or failure behavior when text doesn't match, keeping it from a 5.

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?

Front-loads the 'Free.' cost signal and the core transformation in the first clause, then the downstream consumers. The trailing snippet-syntax example is dense but earns its place; the parenthetical value list is slightly redundant with the schema examples.

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?

No output schema exists, so the description must describe returns, and it does: filter options with IDs plus a filter_snippet. For a 3-parameter read-only lookup tool, that is nearly sufficient; only unmatched-text behavior is 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%, so the schema already documents text, filter_type, and card_no, including the omit-to-list-all behavior for enum types. The description's inline examples ('Shanghai', 'Medical Device', 'CEO') reinforce the text parameter but add little beyond the schema, so baseline 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?

The description uses a specific verb ('Turn a human filter value... into search filter options with IDs') plus a distinct second output (a ready-to-paste filter_snippet). It names the sibling consumers (search_leads, search_companies, create_search_task), so an agent can place it in a workflow without opening anything else.

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 clearly situates the tool upstream of the search/create_task tools and shows the combine syntax for snippets, which is real usage guidance. It does not state when to skip this tool (e.g., when you already have filter IDs) or name an alternative, so it stops short of a 5.

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