AI agents use claude_code_update_api_key to create or update resources in Sage MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Sage MCP environment.
This tool modifies (rather than deletes) an API key, which is security-sensitive data. Update operations are categorized as Write. Severity is high because: (1) API keys control access to services; (2) an incorrect update could lock out legitimate users or enable unauthorized access; (3) the impact is reversible if the correct key is re-applied.
From the tool's definition Tool name contains 'update' and description states 'Update an API key', indicating modification of authentication credentials.
Documented attack patterns abuse exactly the kind of access claude_code_update_api_key gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Sage MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for claude_code_update_api_key:
{
"version": "1",
"default": "deny",
"tools": {
"claude_code_update_api_key": {
"limits": [
{
"counter": "claude_code_update_api_key_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}claude_code_update_api_key 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.
Update an API key. It is categorised as a Write tool in the Sage MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Sage MCP server in PolicyLayer and add a rule for claude_code_update_api_key: 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 Sage MCP. Nothing to install.
claude_code_update_api_key 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 claude_code_update_api_key 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 claude_code_update_api_key. 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.
claude_code_update_api_key is provided by the Sage MCP server (sagemcp/sagemcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 359 Sage MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
359 Sage MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.