discover_devices

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

Annotations cover readOnlyHint and openWorldHint, so the description focuses on the scan algorithm — sequential probing and stop-on-first-miss — which is important non-obvious behavior. It doesn't mention timeouts, error handling, or scan duration, but the core behavioral trait (early termination) is disclosed.

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?

Two tight sentences, front-loaded with purpose then the probing mechanism and downstream use. No filler.

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?

Output schema exists, so return values needn't be described. Given annotations and the simple one-parameter surface, the description covers what's needed to call correctly, though it could note that a full miss-heavy scan may take time or that max_device_id bounds the scan cost.

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 0% and the single parameter max_device_id has only a default of 16, no description. The description implies the parameter is the upper bound of the probe range, which adds some meaning, but doesn't explain the default or valid range beyond the name.

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 (Scan/probe) and resource (Modbus device ids for plant, inverters, DC/AC chargers). It clearly distinguishes itself from read-oriented siblings like get_inverter_status or read_registers by being a discovery 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?

Explains it probes ids 1..max_device_id in order and stops at the first non-answering id, and says to use the result to set environment variables. It doesn't name an alternative tool or say when NOT to use it, but the context of use (bootstrapping configuration) is clear.

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