List Devices

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

No annotations are provided, so the description carries the full disclosure burden. It usefully scopes the result to 'supported by this backend' and lists example vendors, but for a tool sitting next to test_device it never clarifies that listing is passive/non-probing rather than an active hardware check.

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 the resource first and the vendor examples immediately after. No filler, no redundancy.

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?

Because an output schema exists, the description need not describe return values, and for a zero-argument listing tool the remaining burden is small. The only gap is the missing tie-breaker against test_device, which matters more than usual given how similar the two names are.

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 schema has zero parameters, so there is no parameter semantics to convey and the baseline of 4 applies. The description adds nothing here, but nothing is missing either.

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 names a specific resource (EEG devices supported by this backend) and enumerates concrete examples (OpenBCI, Muse, BrainBit, LSL, PiEEG), so an agent knows exactly what set is returned. It does not, however, distinguish itself from the sibling test_device, which is the most likely confusion point.

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 when-to-use guidance and no mention of alternatives. An agent must infer from the name alone that this is the discovery step to run before test_device or start_stream, and nothing in the text confirms or excludes that.

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