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serial.pulse_dtr

Pulses the DTR line low for a specified duration to reset microcontrollers like Arduino or ESP32.

Instructions

Pulse the DTR line: sets low, waits duration_ms, then sets high. Commonly used to reset microcontrollers (e.g. Arduino, ESP32). Check the protocol spec or ask the user before pulsing — effect is device-specific.

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": {
      "connection_id": "<connection_id>"
    },
    "name": "serial.pulse_dtr"
  }
}

Input Schema

Name	Required	Description	Default
`connection_id`	Yes
`duration_ms`	No	Pulse duration in milliseconds (default 100).

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0May 29, 2026

TDQS

A4/5.0

Behavior4/5

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

With no annotations provided, the description effectively discloses the behavioral details: it sets DTR low, waits duration_ms, then sets high. It also notes the effect is device-specific, which adds honesty about variability. This goes beyond minimal transparency.

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

Conciseness5/5

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

The description is extremely concise with two sentences, front-loading the action and then adding important context. Every word adds value without redundancy.

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

Completeness4/5

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

Given the tool's simplicity (2 parameters, no output schema), the description covers the main purpose, use case, and a caution. It is sufficiently complete for an agent to understand and invoke the tool, though it could mention potential side effects or return behavior.

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?

The description reinforces the purpose of duration_ms by saying 'waits duration_ms', but the schema already provides a description for that parameter. The connection_id parameter lacks description in both the schema and the tool description, so the tool description adds no new semantic value for the parameters.

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?

The description clearly states 'Pulse the DTR line' with a specific verb and resource, and describes the sequence (sets low, waits, sets high). It distinguishes itself from siblings like serial.set_dtr and serial.pulse_rts by focusing on pulsing DTR rather than constant set or RTS pulse.

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

Usage Guidelines3/5

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

The description gives a common use case (resetting microcontrollers) and a caution to check the protocol or ask the user before pulsing. However, it does not explicitly mention when to use this tool over alternatives (e.g., serial.pulse_rts) or when not to use it.

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