Agent tools

The agent has file-system access inside a sandboxed stage directory, plus nine Mythos-specific MCP tools. Some are fully wired; some are validating stubs that intentionally do not dispatch.

Filesystem

The agent reads and writes inside an isolated stage directory that mirrors your project. Every file operation is gated by a write-policy check (protected files, path-traversal guards) before it hits disk, then diffed against the previous commit on session end.

  • Glob — find files by pattern.
  • Grep — search file contents.
  • Read — read a file or a range of lines.
  • Edit — replace an exact string.
  • Write — create or overwrite a file (after policy check).

Mythos MCP tools

Nine tools are exposed through a per-session MCP server. The ones with their own page are linked below; the rest (e.g. builder_done) are documented inline in the status table further down rather than as separate pages — there is not enough surface there to justify a dedicated page.

Wired vs stub

Every MCP tool dispatches immediately. db_migrate validates your migration (including the RLS gate) and, when your Supabase project is connected via OAuth, applies it to your database, records the .sql under supabase/migrations/, and regenerates the typed client — so a table and the UI that uses it land in one turn. Destructive DDL and paste-connected projects fall back to a reviewable .sql you apply yourself. The status today:

ToolStatusWhat that means
ask_humanWiredPauses session, waits up to 120 s for your answer. Max 2 per session.
search_pexelsWiredDownloads the image to src/assets/ (Vite) or public/ (Next).
npm_installWiredAppends to package.json (max 10 packages/call, regex allow-list + deny-list, no name@version suffixes). The live preview uses a pre-baked dependency set, so a new package resolves only after you deploy your repo — not in the in-IDE preview.
db_migrateWiredEnforces the RLS gate, then applies the migration to your connected Supabase project, records the .sql + regenerates types. Destructive DDL / paste-connected projects fall back to a .sql you apply via the SQL editor.
auth_patternWiredReturns a short text reminder to use the provider's SDK auth helpers (not ready-to-paste code).
builder_doneWiredRuns the deterministic completeness gate; rejects if App.tsx is not wired or no components exist.

What the agent cannot do

  • Run arbitrary shell commands (no Bash access).
  • Make outbound network calls except through the whitelisted tools.
  • Touch protected files: package.json, tsconfig, vite/next config, .env, .git, scaffold entry files.
  • Exceed 40 turns per scaffold run or 20 per edit (silent loop-guard).
  • Run longer than 480 s for a scaffold or 300 s for an edit (silent wall-clock).

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