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

The annotations already declare readOnlyHint=true, and the description complements this by explaining the z-scored weekly updates, data provenance since 2016, and the returned fields. It also states 'Updates: weekly.' It does not describe the optional 'days' history behavior, but that is covered in the schema, so the description adds behavioral context beyond the annotations.

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 compact and information-dense, covering output, methodology, use cases, and update frequency in three sentences. It front-loads the core return statement, and every clause contributes meaningful context with no wasted words.

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?

Despite lacking an output schema, the description explicitly names the three output fields (divergence_score, risk_neg_density, mda_neg_density) and explains the score range and historical data availability. It covers the tool's core function and use cases adequately, though the optional history parameter's effect is not mentioned in the description (it is in the schema).

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 input schema has 100% coverage for the single optional 'days' parameter, including constraints (1-1825) and a clear description of its behavior and tier requirement. The tool description itself does not add parameter-specific information, so it neither enhances nor diminishes the schema's sufficiency. Baseline 3 is appropriate.

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 clearly states the tool's specific purpose: 'Returns a 0-100 SEC-filing tone-divergence score' with detailed methodology (Loughran-McDonald negative-word density gap between Risk Factors and MD&A sections). It also names the output fields, making it highly specific and distinguishable from generic sentiment tools.

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 explicitly provides 'Call when' scenarios: 'filing sentiment, 10-K/10-Q tone, management burying bad news, or earnings disappointment risk, or when timing pre-earnings position reviews and sell-side alerts on fundamental holdings.' This gives clear context for use. It lacks explicit exclusions or alternatives, but the positive guidance is strong.

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