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

Annotations already cover read-only/idempotent safety, but the description adds substantial behavioral context: cost and key tiers, the 7/30-day retention floors, the since_floor_applied disclosure guarantee against silent truncation, and the etag short-circuit returning unchanged:true.

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-loads purpose and the not-for-discovery constraint, then packs cost/tier and polling mechanics. Dense but every clause carries distinct information; minor compression could improve scanability.

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?

With no output schema, the description still explains return behavior (rows, unchanged:true, since_floor_applied) and the full polling contract, so nothing an agent needs to call it correctly is missing.

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 params are documented; the description still adds cross-parameter workflow semantics (etag pairs with a prior response, since_floor_applied explains a shortened window) that the flat schema entries do not convey.

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?

States a specific verb+resource+scope ('return only the funds whose data changed since a given timestamp') and immediately frames it against discovery, distinguishing it from search_funds by name.

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?

Explicit when-to-use ('FOR STAYING CURRENT, not for discovery'), names the alternative it replaces ('Use this instead of re-running search_funds on a schedule'), and gives the polling workflow condition (send next_since AND etag).

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