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

Annotations already cover read-only, idempotent, open-world, and non-destructive behavior; the description adds useful constraints that the endpoint is id-keyed only and enumerates the deeper field categories returned. It does not discuss errors, rate limits, or authentication, but those are less critical with a single read-only parameter and output schema present.

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?

Three sentences with no filler: purpose, return contents, and prerequisite/constraint. Important information is front-loaded and every sentence earns its place.

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?

For a single-parameter, read-only endpoint with full schema coverage and an output schema, the description covers the necessary calling context: what is returned, how to obtain the id, and what input is not accepted. No critical information for correct invocation 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 a baseline of 3 applies. The description adds value by emphasizing that the param must be an Apollo organization id (not a domain), reinforcing the source endpoints, which is useful beyond the schema's generic string description.

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?

Description opens with a specific resource (complete Apollo record for one company), identifies the key-by identifier (Apollo organization id, not domain), and contrasts with the enrichment sibling by saying it returns 'everything enrichment returns plus deeper fields.' This clearly distinguishes it from get_apollo_organizations_enrich and other 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?

It explicitly tells the agent to first obtain the id from get_apollo_organizations_enrich or post_apollo_mixed_companies_search, and states the endpoint cannot take a domain. This is a clear when/when-not with named alternatives.

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