petromcp MCP server

petromcp

Read well logs with Claude without the data ever leaving your machine.

petromcp is an MCP server for petroleum data formats, built for teams whose files legally cannot be uploaded to a cloud service. No telemetry, no phone-home, no automatic updates, and a default-deny path allowlist that refuses to open anything you have not explicitly permitted. LAS today; DLIS, SEG-Y, and pump cards next.

If you can upload your data somewhere, you have more options than this. If you can't, this was written for you.

What this gives you

LLM hosts cannot read binary or semi-structured petroleum formats. petromcp wraps the established open-source parsers — lasio and dlisio today, with segyio queued for a later slice — and exposes them as MCP tools, so you can have a conversation with your data instead of copy-pasting curve values into chat.

What "local-first" means here, concretely

Not a posture. Four things you can verify in the source:

directory, and every tool routes through one validator that resolves symlinks before checking, so a link inside an allowed directory cannot reach outside it. There is no environment variable that widens the allowlist and no tool that changes it at runtime.

• Default deny. A fresh install can read nothing. Access is granted per

tools ship openWorldHint: false and readOnlyHint: true, so your host can verify that claim rather than take it.

• No network, declared. petromcp opens no outbound connections. All five

name, and the resolved path.

• An audit trail. Every tool call is logged with a timestamp, the tool

original_count, so a 20,000-point log cannot silently dump into a context window.

• Bounded output. Curve reads are capped and report downsampled and

The threat model, and what does not count as a vulnerability, are in SECURITY.md. Read docs/DATA_PRIVACY.md before pointing this at real data — it is authoritative, and if the code contradicts it the code is the bug.

Install

Requires Python 3.10+ and uv.

Add petromcp to your MCP host's config — no clone, no build:

{
  "mcpServers": {
    "petromcp": {
      "command": "uvx",
      "args": ["petroleum-mcp", "serve"]
    }
  }
}

On macOS that file is ~/Library/Application Support/Claude/claudedesktopconfig.json. Restart the host afterwards. macOS notes and troubleshooting: docs/INSTALL.md.

To work on petromcp rather than just use it:

git clone https://github.com/ameyxd/petromcp cd petromcp make setup make install-claude

Configure

By default petromcp can read nothing. Tell it which directories are fair game:

uvx petroleum-mcp config init uvx petroleum-mcp config add-path ~/petroleum/wells

Or, if you want to try it without your own data, generate the synthetic sample from a checkout and allowlist that:

make generate uvx petroleum-mcp config add-path "$(pwd)/examples/sample_data"

Restart your MCP host after editing the allowlist — it is read once at startup.

Use

Open a new conversation and ask, in plain language:

What's wrong with this well log? /path/to/well.las Compare these two wells: /path/to/A.las and /path/to/B.las Convert 1500 psi to kPa.

Claude picks the right tool, reads the file through petromcp, and answers.

Worked examples, with real tool output rather than prose:

density gap, a washout, and a gamma ray spike

• QC a well log — finds a planted

overlap, a missing curve, and a unit mismatch that is invisible in one file

• Compare two wells — depth

files, frames, and what happens when a channel name is ambiguous

• Unit conversion
• Read a DLIS file — logical

Shortened. The full README is on GitHub.