List VISA instruments

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds genuinely non-obvious behavioral context by disclosing that discovery is local-only and that LAN instruments are frequently missed. It doesn't describe output shape, but an output schema exists so that is acceptable.

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 with the scope statement front-loaded and the caveat plus remediation immediately after. Every clause carries actionable information; there is 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?

For a single-parameter, read-only discovery tool with an output schema, the description covers scope, the critical gotcha, and the alternative routes. An agent has everything needed to decide whether to call it and what to do when it returns nothing useful.

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%, so the query parameter, its default, and the SOCKET-hiding behavior are already fully documented in the schema. The description adds no parameter-level detail beyond that, which is the expected baseline when the schema does the work.

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 (discover) and resource (local VISA resources) and enumerates the covered transports (USB, GPIB, serial, some LAN). It also implicitly distinguishes itself from the sibling discover_network_instruments by calling out what it does NOT find.

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?

Explicitly names the failure mode (network oscilloscopes frequently do NOT appear) and routes the agent to two concrete alternatives with the triggering condition: open_instrument by IP for known addresses, discover_network_instruments for network scanning. Nothing is left to inference.

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