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

Annotations declare readOnlyHint=true and destructiveHint=false, so the safety profile is already known. The description adds substantial behavioral detail: rows are recomputed at filing date using facts then available and that day's raw close; split reconciliation affects sample preservation; anchors before unresolved splits are omitted; omissions and missing EV inputs are reported; and missing values are dashes, never estimates. This far exceeds the annotation coverage and gives agents realistic expectations for edge cases.

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?

The description is dense but every sentence carries essential specificity: time range, metrics, recomputation behavior, split handling, output reporting, and missing-value policy. There is no filler or repetition. The most important identifying information is front-loaded in the first sentence, with caveats following in a logical order.

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 tool with one parameter and no output schema, the description covers what the response contains: quarterly rows, metric set, basis labels, split reconciliation effects, omission reporting, and dashed missing values. It also clarifies which sub-populations get special metrics (REITs, verified filers). Nothing essential for an agent to call and interpret the tool is missing.

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?

The schema already fully documents the single ticker parameter with 100% coverage and examples, so the baseline is 3. The description does not add any ticker-specific semantics beyond what the schema provides, but none are needed for a single well-known parameter. There is no gap for the description to compensate for.

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 states a specific verb and resource: retrieving up to ~10 years of quarterly valuation multiples. It enumerates the exact metrics (EV/Revenue, EV/EBIT, EV/EBITDA, P/E, plus REIT and verified-filer variants), which clearly differentiates it from the point-in-time sibling GetValuationMultiples. The name and content together leave no ambiguity about what the tool returns.

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 implies the use case: historical quarterly multiples with a recomputed-at-filing methodology, and it explicitly references the methodology of sibling GetValuationMultiples. It does not explicitly state 'use this for history, use GetValuationMultiples for current,' but the relationship is clear enough from the name and methodology reference. A short when-to-use/when-not-to-use contrast would fully satisfy this dimension.

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