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

Beyond the annotations (readOnly, openWorld, idempotent, non-destructive), the description reveals rich behavior: it fans out to SEC EDGAR, GDELT→GNews fallback, and USPTO; explains the GDELT preference and rate-limit fallback; notes USPTO soft-failure until reactivated; and describes returned data structure (changes[], total_changes, citation URIs).

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 adds value. It front-loads user intents and core capability, then efficiently covers data sources, fallback behavior, parameter syntax, return structure, and a sibling alternative—all in a compact paragraph.

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 no output schema, the description explicitly outlines the return shape and data sources. It covers all key aspects needed for selection and invocation: what it does, how it behaves, parameter formats, fallback logic, and when to choose a different tool. The complexity is high, yet the description is complete.

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 coverage is 100%, so baseline is 3. The description adds meaning by showing the accepted formats for 'since' (ISO date or relative shorthand) and giving concrete examples for 'value' (ticker vs. CIK). It also recommends typical values, exceeding the schema's documentation.

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 concrete user intents ("What's new with X") and defines the tool as a "change feed for a company in the last N days/weeks/months in ONE parallel call." It explicitly contrasts with entity_profile, so it distinguishes itself from a key sibling.

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 provides explicit usage guidance: it tells the user when to use this tool (for real-time change updates) and when to prefer entity_profile (for static profiles regardless of window). It also gives practical parameter advice like "Use '30d' or '1m' for typical monitoring."

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