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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds non-obvious behavior: default sort, the default exclusion of unassigned leads, and the set of fields returned in the result — useful context an agent would otherwise have to infer. Minor tension between 'newest first by default' and the schema's stated order default of 'id'.

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 dense sentences with no filler: scope first, then filters, then the default-exclusion caveat. Every clause carries information an agent needs.

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 15-parameter tool with no output schema, the description usefully lists returned fields and notes the unassigned default, but leaves pagination behavior (limit/offset/next_offset) to the schema. That is acceptable given full schema coverage, though one more sentence on paging would make it complete.

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 15 parameters are already documented, and the description's parameter guidance ('names or ids, not mixed', filter list) largely restates the schema. The 'GET /leads' endpoint note and the unassigned-exclusion default add some value but not much beyond structured fields. 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?

States a specific verb and resource ('List or search sales leads'), clarifies the noCRM.io domain term (opportunities), and enumerates the fields returned. This distinguishes it clearly from nocrm_get_lead (single lead) and nocrm_list_unassigned_leads (unassigned scope).

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 lists every filter dimension (status, step, owner, tags, email, starred, date range) and states that unassigned leads are excluded unless include_unassigned is true, which implicitly routes the agent to nocrm_list_unassigned_leads. It stops short of explicitly naming sibling alternatives such as nocrm_get_lead for single-record lookups.

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