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calibrate_accelerometer

Calibrate the accelerometer to fix 'not level' and 'accel not calibrated' arming blocks. Place the aircraft level, then run to sample and save zero-level to EEPROM.

Instructions

Calibrate the accelerometer (zero-level). Fixes most 'not level' / 'accel not calibrated' arming blocks.

Sends MSP_ACC_CALIBRATION; iNAV samples for ~2s and saves to EEPROM automatically (no reboot).

BEFORE running: set the board/aircraft on a LEVEL surface in its normal flight orientation and DO NOT move it until this returns.

Gates: connected, not armed, confirm=True (dry-run otherwise).

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "calibrate_accelerometer"
  }
}

Input Schema

Name	Required	Description	Default
`confirm`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.5Aug 2, 2026

TDQS

A4.8/5.0

Behavior5/5

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

With no annotations present, the description carries full burden and does well. It reveals the underlying MSP command, the ~2s sampling, automatic EEPROM save, no reboot needed, physical setup requirement, and dry-run behavior based on confirm. This goes beyond the schema and gives the agent critical safety and side-effect information.

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 concise, front-loaded with the purpose, and each subsequent sentence adds necessary detail (protocol, EEPROM persistence, physical prerequisites, gates). The line break for the 'BEFORE running' warning improves scannability.

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?

For a one-parameter, no-output-schema tool, this description covers purpose, usage, procedure, side effects, and preconditions comprehensively. It also distinguishes from its sibling calibrate_magnetometer. No gaps appear for execution.

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

Parameters5/5

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

The single boolean parameter `confirm` is explained: true executes calibration, false performs a dry-run. This adds essential meaning beyond the schema field name 'Confirm', which would otherwise be ambiguous.

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 explicitly names the action and resource ('Calibrate the accelerometer') and ties it to a concrete outcome ('Fixes most 'not level' / 'accel not calibrated' arming blocks'). This clearly distinguishes it from sibling tools like calibrate_magnetometer.

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?

The description states specific conditions for use: when the aircraft has 'not level' or 'accel not calibrated' arming blocks, and provides prerequisites (level surface, don't move, gates). However, it does not explicitly mention when not to use or alternatives such as why_wont_it_arm or diagnose, so it earns a 4.

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