get_contact_score

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds meaningful behavioral context beyond annotations: the dual-mode behavior (single contact vs. lowest-engagement list when contact_id is omitted) and the specific outputs (score, tier, churn risk). No contradictions.

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?

The description is one efficient sentence, front-loaded with the primary action, and each clause earns its place. It communicates both invocation modes and the usage context without any waste.

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 simple tool with one optional parameter, good annotations, and no output schema, the description is quite complete: it names the returned fields, the conditional behavior, and the intended use case. It does not specify response format or limits on the list mode, but these are not essential for a low-complexity read tool.

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%: the single parameter contact_id is described in the schema. The description echoes the schema's note about omitting contact_id, adding no new semantic detail beyond what the schema already provides. Baseline 3 is appropriate.

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 states exactly what the tool does: 'Get engagement score, engagement tier, and churn risk for one contact' and clearly distinguishes the alternative mode when contact_id is omitted. This is a specific verb+resource with two explicit behaviors, making it distinct from sibling tools like get_deliverability_score or get_analytics.

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 includes the explicit usage context 'Use before a re-engagement campaign,' which tells the agent when this tool is appropriate. It does not name alternatives or exclusion criteria, but the clear when-to-use guidance is sufficient for a 4.

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