list_devices

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

With no annotations, the description carries the transparency burden. It makes the read-only nature clear ('List'), explains what will be returned ('discovered and paired devices'), and discloses prerequisites and failure conditions such as installation, accessibility service, and same-network requirements. This is strong, though it could add explicit statements about no side effects or return structure.

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 front-loaded with the main action and then adds a clearly enumerated troubleshooting list. It is somewhat longer than strictly necessary, but every sentence serves a purpose and the numbered steps make it easy to parse.

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?

For a simple list tool with one optional parameter, this description is quite complete: it covers scope, setup prerequisites, and failure behavior. It does not describe the output format, but the absence of an output schema and the straightforward 'lists devices' meaning reduce the severity of that gap.

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 description coverage is 100% and the single optional status parameter is already well documented in the schema. The description adds no parameter-specific detail, but it does not need to because the schema handles it, yielding the baseline score.

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 uses a specific verb and resource: 'List all discovered and paired Android devices running the FreeCode Agent app.' It clearly states the tool's scope, but it does not explicitly differentiate this from the sibling get_device tool, so it stops short of a 5.

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 gives clear context for when to use the tool: to list discovered/paired devices. It even provides troubleshooting steps when no devices appear, which is useful practical guidance. However, it never names alternatives or says when not to use this tool, so it is not a 5.

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