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

readOnlyHint=true already declares the safety profile, so the bar is lower. The description adds the REST mapping (GET /v3/grants/{grant_id}/drafts) which confirms a non-mutating versioned read, but says nothing about pagination behavior, result ordering, or rate limits.

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 endpoint sentence is marginally redundant for an agent but is compact and conveys API versioning; a slightly lower score reflects that it earns its place less than the first sentence.

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?

A simple paginated read whose safety profile is covered by annotations and whose three parameters are fully described in the schema. The only real gap is that the response shape and next_cursor pagination semantics are not surfaced in the description, though page_token's schema text partly covers it.

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, grant_id, and page_token are all fully documented in the schema itself. The description adds no syntax, format, or defaulting detail beyond it, making the baseline 3 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 draft emails') plus the scoping qualifier ('for the connected account'), which implicitly separates it from nylas_list_messages and nylas_create_draft. It never names those siblings explicitly, so an agent distinguishes them only by inference.

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 only implied by the verb and scope — there is no statement of when to prefer this over nylas_list_messages or how to handle a missing grant_id. No exclusions, prerequisites, or alternative selection guidance are provided.

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