stock_exposure_summary

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

No annotations are provided, so the description carries the full behavioral burden. It conveys the shape of the result (per-fund weight, expense ratio, AUM), which is useful, but says nothing about ordering of results, what happens with an unknown ticker, or that this is a read-only lookup. With an output schema present, the return-value gap is forgivable, but the behavioral coverage is thin for an unannotated tool.

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 core action and outputs. The second sentence is partly redundant with the first but earns its place by naming the decision it supports. No filler.

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 a full output schema and 100% parameter coverage, the description need not explain return values or argument formats, and it correctly stays brief. The remaining omission is sibling differentiation in a crowded ETF-tool family, which is a meaningful but bounded gap.

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%: both 'stock' (ticker or name, with examples) and 'limit' (range and default) are fully documented in the schema. The description adds only the meaning of the returned metrics, not new parameter semantics, 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 specific verb and resource ('find the ETFs that give exposure to a stock') and enumerates the returned metrics (weight, expense ratio, AUM), so the agent knows exactly what this produces. It does not, however, differentiate itself from the near-identical sibling find_etfs_holding_stock or from compare_etfs, which leaves a real disambiguation gap.

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 framing question 'what is the cheapest / largest ETF for exposure to X?' implies a use case and hints that this tool is for comparison-style selection. But it never states when to prefer it over find_etfs_holding_stock or compare_etfs, nor any exclusions, so routing must be inferred.

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