list_stim_backends

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

Annotations are absent, so the description carries behavioral disclosure burden. It transparently explains the availability distinction between software vs hardware backends, and mentions that hardware backends must be armed. However, it doesn't disclose details like whether this is a pure read operation or anything about the 'safety ceilings' return value semantics. The description's behavioral content is useful but incomplete for a stateless list operation.

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?

The description is well-organized with a clear lead sentence, a structured breakdown of backend types, and a short return-value note. It's reasonably concise, though it could be trimmed slightly — the format hints like ('log', 'lsl', ...) are valuable and earned their place. The front-loaded purpose makes it skimmable.

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?

There is an output schema, so return values are partially explained by structured data. The description adds the distinction between backend categories and the environment-variable requirement, which is important operational context. The mention of 'safety ceilings' hints at what the returned catalogue includes. For a parameterless listing tool with an output schema, this is reasonably complete, though it could elaborate on what options/safety ceilings mean.

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?

This tool takes 0 parameters with 100% schema coverage (empty schema), so no parameter documentation is needed. The baseline for 0 parameter tools is 4, and the description appropriately covers what the tool returns without needing parameter details.

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 clearly states the tool lists 'stimulation targets, their options, and which ones drive hardware', which is a specific verb (list) + resource (stimulation backends/catalogue). It is well-distinguished from sibling tools like attach_stim_backend, arm_stim, and stim_status, which involve different operations on stimulation state.

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?

The description provides clear usage context by distinguishing software backends (always available: 'log', 'lsl', 'brainflow_marker') from hardware backends that require env var EEG_MCP_ALLOW_HARDWARE_STIM=1 and arming. This tells the agent when this listing is relevant and what constraints apply to the hardware entries. It lacks explicit guidance on when NOT to use it or alternatives, but the context is quite clear.

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