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

The description discloses all key behavioral traits: parallel fan-out to multiple sources, fallback logic (GDELT→GNews), soft-fail for USPTO, return structure (changes grouped by source + total_changes + citation URIs). This is beyond what annotations (readOnly, openWorld, idempotent) provide, adding valuable context without contradiction.

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 fairly detailed but every sentence serves a purpose: purpose, sources, parameters, return structure, and alternative. It front-loads with example queries. Could be slightly more concise but remains well-structured and efficient.

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?

The tool has 3 required parameters, no output schema, yet the description fully covers the purpose, sources, behavior, parameter usage, and return format. It also provides a clear alternative. This is complete for an agent to use correctly.

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% with each parameter described. The description adds value by explaining 'since' with examples and recommended usage, clarifying 'type' is limited to 'company', and specifying 'value' can be ticker or CIK. This enriches the schema definitions.

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 function: 'change feed for a company in the last N days/weeks/months in ONE parallel call.' It lists example queries and distinguishes from sibling tool 'entity_profile' by specifying that the latter is for static profiles, not time-windowed changes.

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 guidance on when to use this tool vs 'entity_profile' and recommends using '30d' or '1m' for typical monitoring. It does not explicitly list all cases where the tool should not be used, but the alternative is clearly defined.

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