idn

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

With no annotations provided, the description carries the full burden of disclosing behavior. It does so thoroughly: it states that the tool always returns the connection block even if the *IDN? query fails, and that the error is included to aid troubleshooting. It also lists the contents of the connection block (transport, env vars, backend hint, resource string, session state, dialect driver) and warns against concurrent calls. This goes beyond a simple 'returns IDN' statement and gives the agent useful behavioral context.

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 somewhat long but every sentence earns its place. It front-loads the purpose and return value, then addresses the failure scenario and the concurrency constraint. It is well-structured with clear cause-effect reasoning, and there is no redundancy or 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?

Given that there is no output schema and no annotations, the description must fully inform the agent about what to expect. It does: it lists the connection block contents, explains the *IDN? query, describes failure behavior, and gives ordering guidance. An agent can call this tool confidently without needing to inspect any other metadata. This is complete for a diagnostic tool.

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 tool has zero parameters, so there is nothing for the description to add beyond the schema (which already covers everything). The baseline for 0 parameters is 4, and the description appropriately does not waste space on parameter details. It focuses instead on output and usage, which is correct.

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's purpose: 'Identify the instrument and report connection details.' It specifies the resource (instrument connection) and the action (identify/report), and distinguishes itself from the sibling tools, which are all measurement/control operations. The tool is positioned as a connectivity/diagnostic first step, so an agent can immediately recognize its role.

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 explicitly instructs when to call it: 'Call this first to verify connectivity and confirm the correct driver was selected.' It also provides a when-not-to-call constraint: 'Do not call concurrently with any other rigol tool.' Additionally, it explains how to interpret failures, telling the agent to check LAN-vs-USB misconfig or unreachable IP before assuming the scope is broken. This is clear, actionable guidance.

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