bb_write_file

THE RISK

Medium Risk

Why bb_write_file needs a policy

This tool modifies repository files but does not delete or destroy data. The action is reversible (files can be overwritten or reverted). While it affects code artifacts and could introduce bugs or malicious code if misused by an agent, it remains in the Write category.

From the tool's definition Tool name 'bb_write_file' and description 'Write/update a file in a Bitbucket repository' clearly indicate creation and modification of data (files). The description explicitly states 'Write/update', which is reversible and non-destructive.

Documented attack patterns abuse exactly the kind of access bb_write_file gives an agent:

POLICY

How to control bb_write_file

PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Bitbucket Python, and nothing reaches the server without passing your rules. This is the rule we recommend for bb_write_file:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "bb_write_file": {
      "limits": [
        {
          "counter": "bb_write_file_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

bb_write_file stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

Create a free account and register MCP Bitbucket Python — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More MCP Bitbucket Python tools

Destructive bb_delete_file Delete a file from a Bitbucket repository Destructive bb_delete_issue Delete an issue from a Bitbucket repository Destructive bb_delete_repository Delete a repository from Bitbucket Write bb_create_branch Create a new branch in a Bitbucket repository Write bb_create_issue Create an issue in a Bitbucket repository Write bb_create_pull_request Create a new pull request in a Bitbucket repository Write bb_create_repository Create a new repository in Bitbucket Read bb_read_file Read a file from a Bitbucket repository

All 10 MCP Bitbucket Python tools →

Write tools on other servers

M-Team MCP Server download_torrent YouTube MCP Server generate_video_title Android Forensics ADB MCP Server combine_reports 0xarchive web3_signup

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Argument validation → Checking tool call arguments against schema and policy before they run.
Scoped token → Per-person credentials that grant a defined subset of servers and tools.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about bb_write_file

What does the bb_write_file tool do? +

Write/update a file in a Bitbucket repository. It is categorised as a Write tool in the MCP Bitbucket Python MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on bb_write_file? +

Register the MCP Bitbucket Python MCP server in PolicyLayer and add a rule for bb_write_file: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches MCP Bitbucket Python. Nothing to install.

What risk level is bb_write_file? +

bb_write_file is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit bb_write_file? +

Yes. Add a rate_limit block to the bb_write_file rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block bb_write_file completely? +

Set action: deny in the PolicyLayer policy for bb_write_file. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides bb_write_file? +

bb_write_file is provided by the MCP Bitbucket Python MCP server (kallows/mcp-bitbucket). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every MCP Bitbucket Python tool call.

Start from MCP Bitbucket Python, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →