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shell-is-all-you-needGive AI tools, not a blank shell

Turn fixed process invocations into focused MCP tools with explicit inputs, filesystem boundaries, resource limits, and durable tasks.

shell-is-all-you-need

From command to MCP tool

This definition exposes cargo fmt as a no-argument tool. The child process is launched directly—there is no shell unless you explicitly configure one.

sh
shell-is-all-you-need \
  --tool \
  --name format \
  --description "Format the Rust workspace." \
  --input-schema '{"type":"object","properties":{},"additionalProperties":false}' \
  --process-timeout-ms 120000 \
  --exec cargo fmt --all

Design principle

Start with the narrowest useful command. Add typed inputs and permissions only when the tool needs them.

What you control

LayerControls
Model contractName, description, closed JSON Schema
InvocationFixed executable and argument templates
FilesystemPath fields, allowed roots, denied paths
ResourcesTimeout, output bytes, concurrency, request rate
Long-running workTask store, polling interval, retention TTL

Build your first tool →

Released under the MIT License.