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

No annotations are provided, so the description must carry the full behavioral burden. It does not disclose whether this is read-only, whether it has side effects, what 'smallest' is measured by, or what it returns. A selection tool with zero annotation coverage should explain more.

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?

A single front-loaded sentence with no filler. It is appropriately sized for a one-parameter tool.

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 annotations and no output schema, the description should explain selection criteria, return format, and what 'smallest' means. Instead it leaves the agent guessing about the matching logic and the result, which is inadequate for a tool whose main job is selection.

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%, so the schema already documents the single 'need' parameter. The description adds only a slight qualifier ('deterministic task') beyond the schema's 'What the agent needs to accomplish.' Baseline 3 is appropriate when the schema does the heavy lifting.

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 states a specific verb ('Choose') and resource ('HumanMirror x402 service') with a clear scope ('smallest ... for a requested deterministic task'). It distinguishes itself from siblings like list_ and get_ by implying a selection/matching operation, but the term 'smallest' is ambiguous and never defined.

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: it suggests calling this when you have a deterministic task and need to select a service. There is no explicit when-to-use guidance relative to siblings such as list_humanmirror_x402_services, get_humanmirror_x402_service, or humanmirror_x402_execute.

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