Find cards within a mana value range, optionally filtered by color and type.
AI agents call search_by_cmc to retrieve information from Scryfall MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves card information based on search filters (CMC/mana value range, color, type). It has no side effects—it only reads and returns data from the Scryfall API. It fits the Read category: search/query/get operations with no capability to modify, delete, or execute code. The blast radius of misuse is minimal, as an AI cannot cause harm by retrieving filtered card data.
From the tool's definition Tool performs a search query on Magic card data filtered by mana cost, color, and type parameters. Description explicitly states 'Find cards' which is a retrieval operation. No modification, deletion, or execution of external operations is mentioned.
Attacks that exploit this kind of access
Find cards within a mana value range, optionally filtered by color and type. It is categorised as a Read tool in the Scryfall MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Scryfall MCP Server MCP server in PolicyLayer and add a rule for search_by_cmc: 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 Scryfall MCP Server. Nothing to install.
search_by_cmc is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the search_by_cmc 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 search_by_cmc. 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.
search_by_cmc is provided by the Scryfall MCP Server MCP server (latte-chan/scryfall-connector). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
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