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

Annotations already cover readOnly/idempotent/destructive, but the description adds meaningful traits: metadata is real, no fabricated composite score, a real liveness probe, and structured errors. It also states what is returned is the same endpoint/payment fields as inspect_capability, which goes beyond the annotation set.

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?

Front-loaded with purpose and usage, and most sentences earn their place. 'Read-only and idempotent; no side effects' largely restates the annotations, which is the one mildly redundant 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?

With an output schema present, return values need no elaboration, and the description still clarifies the shape of results (same fields as inspect_capability). Usage, error behavior, and safety are all covered for a 2-parameter read tool.

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 both parameters are documented in the schema (sml_ids 2-5, probe default true), so the schema carries the load. The description only implicitly gestures at the probe via 'live'/'real metadata' without explaining the boolean switch or its cost/latency implication.

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 (compare), resource (live SqueezeOS capabilities), and scope (2-5, side by side, real metadata). It distinguishes itself from the single-target sibling 'inspect_capability' by naming what it returns relative to that tool.

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?

Gives explicit context ('when an agent must choose between similar APIs, for example weighing price against coverage') plus a concrete scenario ('compare two web-reader capabilities before routing a research task'). It does not explicitly name when to use inspect_capability or recommend_capability instead, so it stops short of full when-not guidance.

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