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

Annotations already declare the safety profile (readOnly, idempotent, non-destructive, non-open-world), so the bar is lower. The description adds useful context by enumerating the fields returned (ID, name, headline, company, profile URL, gender, email, location), which matters since no output schema exists, though it does not discuss pagination behavior explicitly.

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, front-loaded with the primary action. Slight redundancy between 'browse the contacts of one lead list' and 'List saved contacts in a specific lead list', but overall efficient and well-ordered.

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 tool with full schema coverage and clear annotations, the description completes the picture by naming returned fields in the absence of an output schema. Nothing an agent needs 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%, so all three parameters (list_id, limit, offset) are already documented in the schema. The description adds no syntax, format, or constraint details beyond what the schema provides, 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?

States a specific verb (browse/list) and resource (contacts of one lead list) and clearly delimits scope. It names two siblings it is not (search_crm_leads, list_campaign_queue), so an agent can distinguish it without opening any schema.

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?

Explicitly routes the agent: use this for browsing contacts within a single lead list, use search_crm_leads for CRM-wide search, and use list_campaign_queue for invitation/connection/reply state. When-to-use and alternatives are all stated.

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