siglent-sdg-mcp

scpi_query

Read-only

Send a read-only SCPI query to a Siglent SDG waveform generator and return the response, enabling custom queries beyond the built-in tools.

Instructions

Send a read-only SCPI query to the waveform generator and return the response. Use this as an escape hatch for queries not covered by other tools. The command must be a single SCPI header ending in '?' (e.g. 'C1:BSWV?'); anything that could change instrument state is rejected. Note: CHDR is set to OFF, so responses contain only values (no headers).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "command": "<command>"
    },
    "name": "scpi_query"
  }
}

Input Schema

Name	Required	Description	Default
`command`	Yes	SCPI query command to send (e.g. '*IDN?', 'C1:BSWV?', 'C1:OUTP?')
`timeout_ms`	No	Timeout in milliseconds (default 5000)

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv2.0.4Nov 14, 2026
- removedInput schema / additionalProperties
```
Removed value: -false
```
First observedv1.0.0Aug 9, 2026

TDQS

A4.4/5.0

Behavior5/5

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

Goes well beyond the readOnlyHint annotation: it describes the validation contract (single SCPI header ending in '?', state-changing commands rejected) and the response shape (CHDR is OFF, so values come back without headers). That last detail is exactly the kind of context an agent needs and cannot get from annotations or schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Four short sentences, front-loaded with purpose, then the fallback role, then constraints, then the response-format caveat. Ordering is logical and nothing is padding, though the opening sentence slightly overlaps the title-level framing.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the CHDR-OFF note is essential and supplied; the command validation rule and timeout parameter are covered between description and schema. Nothing an agent needs to invoke this correctly appears to be missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description adds the 'single header ending in ?' constraint on the command string, but it says nothing about timeout_ms or how to size it, leaving that entirely to the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Send a read-only SCPI query to the waveform generator and return the response') and explicitly positions itself against the sibling get_*/configure_* tools by calling itself an 'escape hatch for queries not covered by other tools.' An agent can distinguish it from the named-configuration siblings without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives a clear condition for use (queries not covered by other tools) and a clear exclusion (anything that could change instrument state is rejected). It does not name a specific sibling to prefer, but the routing rule is unambiguous enough to act on.

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