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

The description adds behavioral context beyond annotations: it fans out to SEC EDGAR, GDELT→GNews fallback, and USPTO with a note about soft-failure. It also mentions return format and that it makes 'ONE parallel call'. No contradiction with annotations (readOnlyHint, etc.).

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 moderately long but front-loaded with examples. Each sentence adds value, explaining sources, fallback, and parameter usage. It could be slightly more concise, but overall well-structured without redundancy.

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 no output schema, the description mentions return format: 'structured changes[] grouped by source + total_changes count + pipeworx:// citation URIs'. It covers source behavior and fallback. Missing details like pagination or limits, but sufficient for a tool with 3 parameters.

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%, but the description adds helpful guidance: for `since` it explains relative shorthand like '30d' and suggests typical values; for `type` it notes only 'company' is supported; for `value` it gives ticker/CIK examples. This adds value beyond the schema descriptions.

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 purpose as a change feed for a company over a time window, with examples like 'What's new with X'. It explicitly distinguishes from the sibling tool entity_profile by advising when to use that instead. The verb 'change feed' and resource 'company' are specific.

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 usage context with example queries and specifies the `since` parameter format. It explicitly tells when NOT to use this tool: 'Use entity_profile instead when you want the static profile...'. However, it does not mention other alternatives like deep_research.

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