Adds a single architecture decision record (ADR) to DECISIONS.md. Creates a structured entry with title, context, decision, and consequences sections.
AI agents use add_decision to create or update resources in Project MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Project MCP environment.
This tool creates new structured entries in a documentation file (DECISIONS.md), which is a reversible write operation. It does not delete, execute arbitrary operations, or involve financial transactions.
From the tool's definition Tool description states it "Adds a single architecture decision record (ADR) to DECISIONS.md" and "Creates a structured entry with title, context, decision, and consequences sections." The verb "Adds" and "Creates" indicate data creation/modification.
Documented attack patterns abuse exactly the kind of access add_decision gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Project MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for add_decision:
{
"version": "1",
"default": "deny",
"tools": {
"add_decision": {
"limits": [
{
"counter": "add_decision_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}add_decision 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.
Free to start. No card required.
Adds a single architecture decision record (ADR) to DECISIONS.md. Creates a structured entry with title, context, decision, and consequences sections. It is categorised as a Write tool in the Project MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Project MCP server in PolicyLayer and add a rule for add_decision: 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 Project MCP. Nothing to install.
add_decision 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 add_decision 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 add_decision. 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.
add_decision is provided by the Project MCP server (pouyanafisi/project-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Project MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
42 Project MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.