This record as markdown: /tools/io-github-kivanccakmak-yaver/cf-d1.md
What cf_d1 does on Yaver
AI agents invoke cf_d1 to trigger actions in Yaver. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.
| Parameter | Type | Required | Description |
|---|---|---|---|
query | string | — | |
action | string | Yes | list or query |
database | string | — |
Parameters from the server's own tool schema.
Why cf_d1 is rated High
This tool executes queries against a Cloudflare D1 database. While 'query' might suggest read-only operations, database query tools typically allow arbitrary SQL including DML (INSERT, UPDATE, DELETE) and potentially DDL (DROP, ALTER). Since the description is vague and doesn't restrict to SELECT-only, the most severe applicable category is Execute (with potential for Destructive operations).
From the tool's definition "Query Cloudflare D1 database"
Attacks that exploit this kind of access
The rule that runs cf_d1 safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Yaver, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For cf_d1, this is the rule to start with:
cf_d1 stays usable, but rate-capped: a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Yaver, apply this rule, and every cf_d1 call is checked against it from then on.
Questions about cf_d1
Query Cloudflare D1 database. It is categorised as a Execute tool in the Yaver MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
cf_d1 accepts 3 parameters: query, action, database. Required: action. The full parameter table on this page comes from the server's own tool schema.
Register the Yaver MCP server in PolicyLayer and add a rule for cf_d1: 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 Yaver. Nothing to install.
cf_d1 is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the cf_d1 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 cf_d1. 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.
cf_d1 is provided by the Yaver MCP server (yaver-cli). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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