Add tickers to the user's saved watchlist. Duplicates are skipped.
Part of the TickerDB server.
Free to start. No card required.
AI agents use add_to_watchlist to create or modify resources in TickerDB. 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 add_to_watchlist 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 TickerDB.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"add_to_watchlist": {
"limits": [
{
"counter": "add_to_watchlist_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full TickerDB policy for all 11 tools.
These attack patterns abuse exactly the kind of access add_to_watchlist 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.
Add tickers to the user's saved watchlist. Duplicates are skipped.. It is categorised as a Write tool in the TickerDB MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the TickerDB MCP server in PolicyLayer and add a rule for add_to_watchlist: 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 TickerDB. Nothing to install.
add_to_watchlist 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_to_watchlist 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_to_watchlist. 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_to_watchlist is provided by the TickerDB MCP server (tickerdb-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 11 TickerDB 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.