MCP server for 1C over COM
mcp-1c-com
A Python MCP server connecting to a 1C infobase via V83.COMConnector, with nothing to install inside the base itself
High risk
We rate an entry high when the tool writes to external systems, handles money, production databases or secrets, or runs arbitrary commands. The CLI installs it only with your consent.
Why this level
- execute_script, once protection is disabled, runs arbitrary 1C code via the Выполнить and Вычислить operators
- COM access reads and can write infobase data under the configured user's rights
Install
Manual install
claude mcp add 1c-com -- "<путь>\.venv\Scripts\python.exe" "<путь>\server.py"Command from the README to connect the server to Claude Code.
This is third-party code. Review the repository files before installing.
What it does
The server opens an external COM connection to a 1C infobase and provides five tools: execute_query runs a query in the 1C query language with parameters and a row limit, list_metadata lists metadata objects by kind, describe_object shows an object's attributes and tabular sections with types, connection_info checks the connection and versions, and execute_script runs arbitrary code or evaluates an expression through a separate executor processing object, because a raw external COM connection cannot use the Выполнить and Вычислить operators itself.
Who it is for. For 1C developers on Windows who need MCP access to a base without installing an extension inside the configuration itself.
Good fit when
- You need a quick query against a 1C base without touching the configuration itself
- You need an object's structure by name
- You need to run one-off 1C code through an agent for debugging
Not a fit when
- You are not on Windows: the COM connector is only available there
- You need safety around a production base: execute_script, once security protection is disabled, can run arbitrary code
Example request
Show the structure of the Counterparties catalog and run a query over sales documents from JanuaryLimitations
Works only on Windows with 1C:Enterprise 8.3 installed, and needs matching bitness between Python and comcntr.dll. Reference values in query results come back as UUIDs with no display value unless ПРЕДСТАВЛЕНИЕ is explicitly requested. The execute_script tool requires disabling «Protection from dangerous actions» for the infobase user, which explicitly weakens protection against accidental Выполнить and Вычислить calls.
How to disable. Remove the 1c-com server from the project's .mcp.json, with claude mcp remove 1c-com in Claude Code.
MCP
- Transport
- stdio
- Authentication
- not required
| Environment variables | |
|---|---|
| ONEC_FILE | Path to a file infobase. |
| ONEC_SRVR | Cluster server name for a server infobase. |
| ONEC_PWD secret | Password of the 1C user. |
Security check
- execute_script, once protection is disabled, runs arbitrary 1C code via the Выполнить and Вычислить operators
- COM access reads and can write infobase data under the configured user's rights
README in short
The README lists five MCP tools, Python and comcntr.dll bitness requirements, environment-variable configuration for file and server bases, connecting to Claude Code via .mcp.json, a dedicated section on execute_script with its executor processing object and the need to disable «Protection from dangerous actions», and diagnostics for common COM errors.
FAQ
Why does execute_script need a separate processing object?
Because the Выполнить and Вычислить operators are language constructs, not global-context methods, and a raw external COM connection cannot expose them directly.
What does the TYPE_E_LIBNOTREGISTERED error mean?
The connector's type library is not registered; fix it by re-registering comcntr.dll as administrator.
Related
A skills library that gives coding agents a development process: brainstorming, planning, TDD, subagents and code review
Skills for real engineers by Matt Pocock
Skills For Real Engineers
Small composable skills for engineering with agents: plan grilling, TDD, bug diagnosis, code review and architecture
GitHub toolkit for spec-driven development: the specify CLI adds agent commands and skills to a project, from principles to implementation
Reference MCP servers
Model Context Protocol servers
Official reference MCP servers: Filesystem, Fetch, Git, Memory, Sequential Thinking, Time and Everything