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

Annotations cover the safety profile (readOnlyHint=false, idempotentHint=true, openWorldHint=true), but the description adds behavior those hints cannot: a live external fetch that ingests, immediate return when already present, and a failure taxonomy (NOT_IN_REGISTER, IN_PROGRESS/QUEUE_FULL with retry guidance, SOURCE_UNAVAILABLE) plus malformed-UID rejection.

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?

Four sentences, front-loaded with the action and the prerequisite, then outcome, then status codes. Every clause carries operational information; no filler or repetition of the title.

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 an output schema present, the description needn't detail the record shape, and it correctly focuses on loading semantics and the loadStatus failure modes an agent must branch on. Complete for a one-parameter ingest tool.

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% and the single uid parameter already documents 'formatted or plain'. The description adds marginal but real value by specifying that a malformed UID is rejected rather than silently ignored, which shapes caller validation expectations.

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?

Uses a specific verb+resource ('Fetches a company from SHAB/Zefix live and ingests it') and anchors scope with the sibling prerequisite 'for a UID get_companies reports as notInDataset'. An agent can distinguish this from get_companies, search_companies, and find_company_by_name without opening any schema.

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 states when to use it ('call get_companies first' for a notInDataset UID) and what happens in the already-loaded case ('an already-present UID returns immediately'). Names the alternative tool that selects this path, leaving nothing to inference.

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