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

Annotations are minimal (readOnlyHint=false, destructiveHint=false), so the description carries some burden. It discloses that the action is immediate and unpaid, which adds context beyond annotations, but it doesn't describe side effects, visibility, or pass consumption. No contradiction with annotations.

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 no filler. The action and context are front-loaded; the paid-task caveat is a useful second 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?

Given the output schema exists, the description covers the key distinction (unpaid vs paid) and the required flow (Guest Pass). It doesn't explain the full lifecycle, but sibling tools like nexus_guest_start_pass and the schema fill the gap.

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 coverage is 100% and every parameter has a description, including guest_token's origin from nexus_guest_start_pass. The description adds no parameter-specific meaning, so 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?

The description uses a specific verb ('Post') and resource ('unpaid NEXUS task') with a mechanism ('Guest Pass'), and notes the contrast with paid tasks. It does not explicitly name the sibling tool (e.g., nexus_post_task) but the distinction is clear enough to route correctly.

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?

It provides a clear condition: use this tool for unpaid tasks with a Guest Pass, and notes that paid tasks require durable authentication, implying a different path. It avoids explicit alternative tool names, but the guidance is actionable.

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