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

Goes well beyond the readOnly/idempotent annotations with cost behavior (no lookup credit), fidelity semantics ('as the CRM holds it'), and an explicit prompt-injection guardrail that record text is data, not instruction. That injection warning is exactly the kind of behavioral context an agent cannot infer from 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?

Three short sentences with zero padding; the core action is stated first, followed by cost, the update relationship, and the safety note in descending priority. Every sentence carries distinct information.

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 covering return values and full annotation coverage of the safety profile, the remaining gaps an agent needs — cost, fidelity, downstream mutation relationship, and injection safety — are all addressed. Nothing required to call it correctly 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 description coverage is 100%, with record_id, entity_type, and record_type all documented in-schema, so the baseline is 3. The description adds no further semantics about parameter interaction or defaults beyond what the schema already states.

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 ('Read one person or company record') plus the framing 'as the CRM holds it,' which distinguishes it from enrichment/summary tools. It names the related sibling update_crm_record, though it does not explicitly contrast with search_crm or find_person_in_crm, which also return record data.

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?

'Uses no lookup credit' gives a real selection signal versus credit-consuming lookups, and 'update_crm_record changes only a record read this way' establishes a clear prerequisite workflow. It stops short of stating when to prefer this over siblings like find_contact_details or search_crm.

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