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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds the crucial billing behavior: free, quote-only, never spends credits, and firms not found cost nothing. That is exactly the kind of behavioral fact annotations cannot express and is essential for a credit-based tool.

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, then output content, then the free/quote workflow, then the alternative. Slightly long with some repetition of the firm-type list already in the schema, but every sentence carries routing or billing weight.

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?

Given a quote-then-run two-step flow, four params with full schema coverage, and an output schema, the description supplies everything needed: what it returns (phones, emails, website, names/titles), the credit-safety guarantee, and the required next-step handoff to run_investor_firm_search with quote_id.

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 enums already spell out investorType values and state codes, so the description adds little parameter detail. Baseline 3 is appropriate since the schema does the heavy lifting; the firm-type list in the description is largely redundant with the enum 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?

States a specific verb and resource ('find real estate investor and lender firms') with an explicit enumeration of the firm types covered, which maps to the investorType enum. It also names the sibling tool that serves a different intent (quote_active_investor_search), so an agent can route without opening the 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?

Gives a complete workflow: tell the user the cost, ask, and only then call run_investor_firm_search with the quote_id. It also names the alternative (quote_active_investor_search) for the distinct job of finding active buyers, covering both when-to-use and when-to-use-something-else.

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