set_serial_number

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

No annotations are provided, so the description carries the burden; it does disclose that this changes runtime state and depends on a prior list_devices call. It is silent on whether the setting persists across sessions, what happens with an invalid serial number, and whether an established gdb/rtt connection must be re-established after the change.

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?

Three short sentences, front-loaded with the action, then the condition, then the prerequisite. Every sentence contributes distinct information and nothing is repeated.

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 one-parameter runtime setter with full schema coverage and no output schema, the description supplies purpose, trigger condition, and prerequisite tool. Only failure behavior and persistence/lifecycle effects are missing, which is a minor gap at this complexity level.

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 parameter already documents the accepted format and the empty-string-to-clear semantics. The description only reiterates the source of the value (list_devices) with no added syntax, validation, or edge-case detail, so baseline 3 applies.

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 and resource ('Set the debug probe serial number') and immediately scopes it ('at runtime'), which distinguishes it from configuration-style siblings like set_device or set_svd_path. An agent can tell exactly what state this mutates without opening the schema.

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?

Gives a concrete triggering condition ('Required when multiple probes are connected to select which one to communicate with') and names the prerequisite/alternative tool to consult first ('Run list_devices'). It stops short of saying when the tool is unnecessary (e.g. single probe, or an active session needs reconnecting), so not a full 5.

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