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

Annotations already carry the safety profile (readOnly, idempotent, non-destructive, open-world), so the bar is lower. The description adds genuinely useful non-annotation context: BYOK key handling, a cost model (1 credit per page), and a cap (up to 10,000 postings), which an agent needs to reason about invocation volume.

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 the purpose, then prerequisite, then cost, then a concrete call example. Every sentence earns its place, though it is on the longer side; the example is useful rather than filler.

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 compensates by naming the returned field categories and the volume cap, and it covers prerequisites and cost. Complete enough to invoke correctly, missing only edge cases like empty results or error behavior.

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 all four parameters are already documented, establishing a baseline of 3. The description reinforces organization_id sourcing and BYOK for _apiKey and implies page-level costing, but adds little syntax or format detail beyond what the schema provides.

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 (List) and resource (a company's current job postings) and enumerates the returned fields (title, location, posted/last-seen dates). It also frames the analytical purpose (headcount growth signal), which lets an agent distinguish it from generic search/enrich siblings.

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 the prerequisite: an Apollo organization_id must be obtained from apollo_search_organizations or apollo_enrich_organization first, naming the alternatives that produce it. It stops short of stating when NOT to use this tool, so it lands at 4 rather than 5.

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