Start scan

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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the safety profile is covered. The description adds little beyond the HTTP verb/path: it does not say whether the scan is long-running, whether it must be polled via get_lineup_status, whether a scan in progress blocks a second call, or what happens if the optional source is omitted.

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?

One compact line with the action front-loaded after the endpoint template; nothing is padded. It is arguably too terse for the omitted workflow context, but as a structure it is efficient and scannable.

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 state-changing, non-idempotent device operation with no output schema and an undocumented parameter warrants more explanation: scan duration, how to observe progress, and the abort path. The description leaves the agent to guess the surrounding workflow.

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?

The single parameter has 0% schema description coverage, and the description only hints at optionality via the bracket notation '[&source=<Source>]' without explaining valid values or the default behavior. Since the tool has a parameter, the baseline-4 rule for zero-param tools does not apply, and the description does not compensate for the coverage gap.

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 and resource ('begin a channel scan') and even maps it to the underlying endpoint, so an agent knows exactly what operation this performs. It stops short of differentiating from the obvious sibling hdhomerun_abort_scan or from status-checking tools like hdhomerun_get_lineup_status.

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?

There is no guidance on when to start a scan versus when to abort or check progress, and no prerequisites or preconditions are stated. The presence of hdhomerun_abort_scan and hdhomerun_get_lineup_status as siblings makes the omission costly, since the agent must infer the workflow.

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