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

Annotations already mark read-only/idempotent/non-destructive, but the description adds substantial behavioral traits: parallel fan-out to three sources, GDELT preferred over GNews with fallback on rate-limit/5xx, USPTO soft-fail due to PatentsView sunset, and the shape of the return (changes[] grouped by source, total_changes, pipeworx citation URIs). No 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?

Front-loaded with query examples and functional summary, then details sources and return shape. Dense but every sentence carries useful info. Slightly long for a single paragraph, yet well organized; could be split for readability, but not wasteful.

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?

High complexity tool (3 sources, fallbacks, time-window parsing, citation URIs) with no output schema. Description covers input semantics, source behavior, fallback logic, and return structure (changes[] grouped by source, total_changes, pipeworx:// URIs). Adequate for an agent to invoke and interpret 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?

Schema coverage is 100%, but description enriches meaning: explains since accepts ISO date or relative shorthand with concrete examples ('7d', '30d', '3m', '1y'), clarifies value can be ticker or zero-padded CIK, and notes type currently only supports company. This goes beyond the schema's field 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 opens with concrete user intents ('What's new with X', 'latest on Y') and then states the core function: a change feed for a company over a time window. It clearly names the resources (SEC EDGAR, GDELT/GNews, USPTO) and distinguishes itself from sibling entity_profile by contrast.

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?

Explicitly gives when to use (change feed for a company in last N days) and when not to use ('Use entity_profile instead when you want the static profile'). Also provides typical usage examples and explains fallback behavior across sources, which helps the agent decide.

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