Send a transaction that has already been signed and serialized into the wire format.
AI agents use send_transaction to create or update resources in Model Context Protocol Server for Solana Client — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Model Context Protocol Server for Solana Client environment.
An AI agent can call send_transaction faster than any human can review — one bad instruction and it creates or modifies resources in Model Context Protocol Server for Solana Client by the hundred, each call as confident as the last.
Attacks that exploit this kind of access
Send a transaction that has already been signed and serialized into the wire format. It is categorised as a Write tool in the Model Context Protocol Server for Solana Client MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Model Context Protocol Server for Solana Client MCP server in PolicyLayer and add a rule for send_transaction: 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 Model Context Protocol Server for Solana Client. Nothing to install.
send_transaction 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 send_transaction 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 send_transaction. 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.
send_transaction is provided by the Model Context Protocol Server for Solana Client MCP server (tywenk/mcp-sol). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.