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

The description goes well beyond the annotations (readOnlyHint, idempotentHint, destructiveHint) by disclosing that it 'performs bounded internal fan-out, preserves partial failures, and explicitly reports missing evidence instead of inventing' facts. It also states the server-enforced evidence plan, which is critical behavioral context for an agent deciding whether to invoke.

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 a single dense paragraph, but it is well-organized: purpose, parameter summary, behavior, and use case. It could be slightly more scannable with bullets, but every sentence earns its place and there is no filler. The length is justified given the tool's composite nature.

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?

Given the tool's complexity (7 params, composite workflow, output schema present), the description covers all necessary context: when to use, what evidence plan is included, parameter roles, behavior (read-only, idempotent, partial-failure handling), and what the report explains. It also addresses missing evidence behavior, which is important for an agent's trust and interpretation of results.

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?

While the schema already describes each parameter with 100% coverage, the description adds valuable semantic context by grouping them as 'reproduction controls' and noting that 'ticker is required and normalized to uppercase.' This adds meaning beyond the property-level descriptions, though it does not fully rewrite their syntax.

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 opens with a specific verb+resource+context: 'Use this read-only composite workflow tool for a paid filing-backed issuer drilldown when a daily brief pressure or opportunity row needs causality.' It clearly distinguishes itself as a composite drilldown tool (not a single-slice lookup) and explains the scenario where it applies.

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 gives explicit when-to-use guidance: 'when a daily brief pressure or opportunity row needs causality, not just a headline score.' It also clarifies the intended use case ('GME-style paid reports') and lists the incorporated evidence areas. However, it does not explicitly name when not to use it or point to alternative sibling tools, so it stops short of a full 5.

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