{"version":"2.1.272","anchor":"appifactrepl-tool-a-full-js-repl-tool-for-filling-artifacts","canonical_anchor":"appifactrepl-tool-a-full-js-repl-tool-for-filling-artifacts","heading":"New AppifactRepl tool for building artifacts via a JavaScript REPL","tier":"soon","area":"Artifact REPL","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.272\/e\/appifactrepl-tool-a-full-js-repl-tool-for-filling-artifacts","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.272","markdown":"### New AppifactRepl tool for building artifacts via a JavaScript REPL\n\nA new AppifactRepl tool runs JavaScript against an Artifact's data (a REPL, or read-eval-print loop) but is currently gated off for most users\n\n**Unclear.** Whether `isAppifactReplToolEnabled()` defaults to true or false cannot be determined, since its code lives outside this bundle.\n\n**What**\n\n- A new tool called `AppifactRepl` runs a full Node.js REPL (a read-eval-print loop, meaning it executes a whole JavaScript program and returns the result) against an Artifact's document store, via `claude.use(\"db\")`, `claude.use(\"files\")`, and `claude.use(\"assets\")`, instead of making one Artifact store call at a time. It also supports `claude.see()` for attaching images or text to the tool's result, and can run a skill's own SDK script instead of the built-in one.\n\n- Internally it spawns a child process (running `node scripts\/appifact_sdk.js --repl -`) in a sandbox, and its output is scrubbed before being returned.\n\n- The tool is wired into the permission system, the always-allowed tool list, tool-name resolution caching, and file-read tracking. A permission-check helper adds a special case for it: it is treated as disabled if there is a matching deny rule, or a permission rule whose content is only whitespace or asterisks.\n\n- Writes made through `AppifactRepl` do not trigger the automatic artifact-opening behavior that normal file writes do.\n\n- The tool is gated behind multiple conditions: it only activates when the app is launched with the `remote_cowork` entry point, an internal flag (`tengu_buzzing_lightning`, defaulting to false) is enabled, and a further enablement check (`isAppifactReplToolEnabled()`) whose implementation lives outside the shipped bundle and can't be fully inspected from source.\n\n**Why**\n\nThis is groundwork for a more powerful way to build artifacts step by step with real code instead of individual tool calls, but it is not yet available to regular users: it's gated behind a server-side flag and only activates in the `remote_cowork` context, so most users won't see or be able to use it yet.\n\n- Area: Artifact REPL\n- Tier: Nothing to try yet\n- Useful: 5\/5\n- Signal: 5\/5\n- Present in the build but not switched on"}