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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds value by specifying 'non-persistent, immediately complete synthetic session', which clarifies side effects and the nature of the output. This extra context goes beyond the annotations without contradicting them.

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?

Two short sentences with zero filler. The purpose is front-loaded, and the second sentence adds key behavior details (non-persistent, synthetic) without redundancy. Every word 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 two-optional-parameter tool with a clear output schema and annotations, the description is adequate. It conveys the essential purpose and behavior. It does not explicitly draw the contrast with the record-retrieval siblings, but the purpose statement is sufficient given the structure. A slightly more explicit usage note would make it a 5.

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?

Both parameters are already fully described in the schema (categories enum and external_user_id pattern, maxLength, and explicit guidance to not use real patient identifiers). The description adds no parameter-specific insight, so it remains at the baseline of 3 given 100% schema description coverage.

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 purpose: 'Use this to prototype the FinchNode connection journey.' This clearly distinguishes it from sibling get_demo_* tools, which retrieve specific record categories. The verb 'prototype' and resource 'connection journey' are precise and non-tautological.

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?

The description frames it as 'Use this to prototype...', implying it is for the connection journey rather than for retrieving records, but it does not explicitly compare to alternatives or state when not to use it. Given the sibling set of get_demo_* tools, the usage is implied but not articulated.

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