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

Annotations already declare readOnlyHint=true and openWorldHint=true, but the description adds rich behavioral context: it covers a five-quarter window, reads from filings and exhibits, cites SEC accession numbers, returns the full digest by default (calling it 'short'), and allows narrowing via a section. This goes well beyond the annotations and tells the agent exactly what to expect.

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 sentences, no fluff. The first sentence front-loads the core purpose and content; the second explains the default return and the optional narrowing. Every clause carries information, and the description is appropriately sized for the tool's complexity.

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 no output schema, the description explains what is returned (a digest) and its scale ('short'), plus the trailing five-quarter span and the source (filings and exhibits). It covers the parameter semantics, the default behavior, and the optional narrowing. Nothing an agent needs to call it correctly is left unspecified.

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 covers 100% of parameters (ticker and section) with clear descriptions. The description adds the purpose of the section parameter ('Pass a section to narrow it'), reinforcing its role. Since schema already documents case-insensitivity and prefix matching, the description's extra value is the 'narrow' intent, earning a 4 above the baseline 3.

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 'get' and a precise resource: 'Digest of a company's material current reports (Form 8-K)'. It distinguishes itself from siblings by naming the SEC form and listing concrete event types (earnings releases, management changes, etc.), so an agent knows exactly what this tool provides compared to get_financials or get_narrative.

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 when to use it (when you need a digest of material 8-K events) but never explicitly contrasts it with siblings or states when not to use it. It provides usage context through the time range and the 'narrow it' instruction, but lacks a clear alternative-selection rule.

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