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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered by structured data. The description adds account scoping ('the account's saved') and downstream applicability, but says nothing about ordering, pagination, or what the criteria objects look like.

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 the purpose front-loaded and no filler. The second sentence is a lowercase fragment ('the selectable source for...') that reads as a stray clause, but it still earns its place by conveying downstream use.

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 read-only list with one fully documented optional parameter and no output schema, the description covers purpose and downstream use. It leaves gaps on return shape (what a 'mixed criteria' entry contains) and whether all criteria are returned regardless of the qualified flag.

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% and the single optional boolean 'qualified' is fully documented in the schema as filtering to qualified-signal fields. The description adds no interpretation of 'qualified' or of the default behavior when omitted, so baseline 3 applies.

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?

Names a specific verb+resource ('List the account's saved Salesforce mixed criteria') and disambiguates the resource via a parenthetical gloss ('contact-list criteria'). It also positions the result as the source for creating a Salesforce-contacts audience, which separates it from list_segments, list_audiences, and search_ma_lists.

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 phrase 'the selectable source for creating a Salesforce-contacts audience' implies the intended downstream workflow, so an agent can infer when to reach for it. But there is no explicit when/when-not guidance and no named alternative (e.g., list_segments or search_ma_lists) for other criteria types.

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