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

Annotations already flag destructiveHint=true and readOnlyHint=false, and the description explains why: a matched property consumes one property credit and contacts consume people credits, with no charge on a miss. It also discloses the auth requirement (connected account with paid access) and that DNC flags accompany phone numbers — real context beyond the structured fields.

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 tight sentences: purpose and input modes first, then output shape, then the contact gating rule, then cost and prerequisites. No filler, and the credit-cost warning is placed where an agent will see it before invoking.

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 credit-consuming, 7-parameter tool with no output schema and destructiveHint=true, the description covers auth, cost, no-match behavior, and what gets returned. The only gap is that it never explains the 'fields' filter or the relative cost of the owners_and_family/renters/residents audience values.

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 the baseline is 3. The description adds meaningful semantics for contact_audience, explaining that contacts are omitted unless it is set and that 'none' costs zero people credits, but it says nothing about the 'fields' array parameter that controls which property fields are returned.

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?

The description opens with a specific verb and resource: 'Finds who owns a US property from its street address', and enumerates the accepted address input modes. That address-keyed framing implicitly separates it from siblings like dealmachine_enrich_apn and dealmachine_enrich_latlng, though no sibling is named explicitly.

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?

Usage conditions are implied rather than stated: a connected DealMachine account with paid access is required, and contacts only come back when contact_audience is set. Nothing tells the agent when to prefer this over the APN- or lat/lng-based enrichment siblings, so routing between them is left to inference.

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