Propose a replacement for an anchored section of an agent template doc (CLAUDE.md or AGENTS.md). Does NOT write the file directly — it creates a human-in-the-loop request carrying a diff preview. A human approves it in the dashboard, then Meridian replaces that section and stages the file for the...
Risk signalsAccepts file system path (file) · Accepts raw HTML/template content (content)
Part of the Meridian server.
Free to start. No card required.
AI agents use update_md_section to create or modify resources in Meridian. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call update_md_section repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Meridian.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"update_md_section": {
"limits": [
{
"counter": "update_md_section_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Meridian policy for all 42 tools.
These attack patterns abuse exactly the kind of access update_md_section gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Propose a replacement for an anchored section of an agent template doc (CLAUDE.md or AGENTS.md). Does NOT write the file directly — it creates a human-in-the-loop request carrying a diff preview. A human approves it in the dashboard, then Meridian replaces that section and stages the file for the next checkpoint commit. 'anchor' is the section name between the MERIDIAN:ANCHOR:START/END comments. (ROADMAP/DECISIONS/DEVLOG are append-only and not replaceable.). It is categorised as a Write tool in the Meridian MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Meridian MCP server in PolicyLayer and add a rule for update_md_section: 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 Meridian. Nothing to install.
update_md_section is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the update_md_section 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.
Set action: deny in the PolicyLayer policy for update_md_section. 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.
update_md_section is provided by the Meridian MCP server (@meridianmcp/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 42 Meridian tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.