ignition-mcp

Overview Schema Source Related Servers Discussions Admin

tag_write

Write tag values to Inductive Automation Ignition by specifying a path and value for each write. Confirm writes to prevent unintended changes.

Instructions

Mutating, bridge plane. Each write dict: {"path": str, "value": Any}.

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": {
      "writes": "<writes>"
    },
    "name": "tag_write"
  }
}

Input Schema

Name	Required	Description	Default
`writes`	Yes
`confirm`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Jul 5, 2026

TDQS

D1.5/5.0

Behavior1/5

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

No annotations provided, so description must disclose traits. Only says 'Mutating' implying state change, but no details on permissions, side effects, error handling, or output behavior.

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

Conciseness2/5

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

Extremely short but cryptic. Lacks clarity and structure; the term 'bridge plane' is unexplained. Not efficiently communicating purpose.

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

Completeness1/5

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

Given two parameters, output schema, and a suite of sibling tools, the description is far from complete. No explanation of how writes are applied, atomicity, or integration with other tools.

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

Parameters2/5

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

Schema coverage is 0%, but description adds minimal info: 'each write dict: {"path": str, "value": Any}'. Does not explain the 'confirm' parameter or the full structure of writes.

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

Purpose2/5

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

Description states 'Mutating, bridge plane' which is vague and non-standard. Does not clearly indicate that this tool writes tags, though siblings like tag_read suggest it. Lacks specific verb+resource combination.

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

Usage Guidelines1/5

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

No guidance on when to use this tool vs. alternatives like tag_create or tag_browse. No mention of prerequisites 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.