Save the user's travel profile locally for future sessions. Call this after asking the user for their details (name, date of birth, reduction card). Data is stored at ~/.sbb-mcp/profile.json.
Part of the Sbb server.
Free to start. No card required.
AI agents use save_profile to create or modify resources in Sbb. 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 save_profile 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 Sbb.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"save_profile": {
"limits": [
{
"counter": "save_profile_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Sbb policy for all 9 tools.
These attack patterns abuse exactly the kind of access save_profile 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.
Save the user's travel profile locally for future sessions. Call this after asking the user for their details (name, date of birth, reduction card). Data is stored at ~/.sbb-mcp/profile.json.. It is categorised as a Write tool in the Sbb MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Sbb MCP server in PolicyLayer and add a rule for save_profile: 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 Sbb. Nothing to install.
save_profile 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 save_profile 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 save_profile. 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.
save_profile is provided by the Sbb MCP server (fabsforward2-zhoi/sbb-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 9 Sbb 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.