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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, so the safety profile is covered. The description adds genuinely useful behavior: results are ordered newest first and contacts are auto-created from incoming messages and new leads, explaining why no create path exists — a trait not expressed in the 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?

Short and front-loaded: identity first, then ordering, then the auto-creation caveat. The opening line duplicates the title verbatim, which is the only wasted text.

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 no output schema, the description supplies the one return-shape fact an agent needs (newest first) while the schema handles all filter and pagination semantics. Nothing essential for calling the tool 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 limit, cursor, search, channel, date_from and date_to are already fully documented in the schema, including clamping and error behavior. The description adds no parameter-level meaning, so the 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 and resource (list an agent's contacts) and frames the entity as 'the people behind the agent's conversations and leads, newest first'. The note that there is no create endpoint cleanly separates it from creation-side siblings like create_lead, though it never explicitly contrasts with get_contact or list_leads.

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?

Usage is implied rather than stated: the agent learns it can only read contacts that Mojeeb auto-generates, but there is no explicit guidance on when to prefer list_contacts over get_contact, list_leads, or list_contact_notes, and no when-not conditions. Adequate but with clear routing gaps.

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