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

Annotations already carry readOnlyHint=true and destructiveHint=false, so the description is rightly not burdened with the safety profile. It adds genuinely useful behavioral context beyond the schema: 'A stock missing a bounded metric is excluded', paging behavior, default sort, inclusion of dataset vintage, and that sorting/filtering on a metric adds it to the result table. These materially shape agent expectations.

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?

A tight four-sentence paragraph that front-loads the tool's purpose, then packs the essential behavioral rules (exclusion, sort, paging, vintage, result augmentation). For a 38-parameter tool, it wisely avoids restating every field and every sentence earns its place.

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?

For a complex 38-optional-parameter screener with no output schema, the description covers the decision-critical facts an agent needs: filter categories, exclusion semantics, sort/paging behavior, and result composition. It stops short of describing the exact response shape or accepted sort-key enumeration, but those are minor against the breadth already disclosed.

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% with strong per-parameter descriptions (units, examples, ranges, and domain notes like '0 keeps profitable companies only'). The description groups parameters into categories but adds no per-parameter meaning beyond the schema — this matches the baseline of 3 for full-coverage schemas.

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+resource ('Screen listed stocks') and enumerates the full filter surface: price, market cap, institutional ownership, short data, insider activity, valuation, growth, margins, liquidity, earnings. This clearly distinguishes it from single-metric siblings like GetShortInterest or GetInsiderOwnership, which are narrower point lookups.

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 description makes the general purpose obvious — breadth multi-criteria filtering across listed stocks — but it never names alternative tools or states when NOT to use it (e.g., for single-instrument facts, use GetFinancialFact/GetLatestClosingPrices). Usage context is implied rather than explicit, and no exclusions or routing guidance is given.

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