Best value under budget

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

Annotations already cover read-only/idempotent/open-world, but the description adds real behavioral context: ranking is by price reach/popularity/cheapness because Torob has no quality score, only in-stock products with at least `min_shops` shops are returned, and it explains the `budget_used_pct` computed value. It stops short of describing output shape or pagination.

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?

Three front-loaded sentences with no filler; the core purpose leads and caveats follow. Fairly dense with parenthetical asides but each sentence carries information, so nothing is wasted.

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 86% schema coverage, no output schema, and full annotations, the description fills the remaining gaps: ranking rationale, in-stock/min_shops constraint, and sibling handoff to tb_compare. A brief note on return shape would make it fully self-sufficient.

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 86%, so the enum semantics for rank_by, condition, and min_shops are already documented in the schema. The description largely restates these ("at least `min_shops` shops") and adds little new parameter meaning beyond the structured data, so the 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?

States a concrete verb+resource (rank product picks under a budget) and anchors it with an example query ("best phone under 30 million"). It also routes to tb_compare for spec checking, but does not explicitly distinguish itself from sibling listers like tb_cheapest or tb_search.

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 example query gives a clear when-to-use scenario (budget-constrained "best X under Y" shopping), and it tells the agent to follow up in tb_compare to check specs. No exclusions or explicit comparison against the search/cheapest siblings are given.

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