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PLATFORM_SPEC.md — Replit (Replit Agent / cloud IDE)

New to gald3r on this platform? Start at Use gald3r with Replit Agent for a short overview before the full breakdown below.

Replit Agent is an AI coding agent built into the Replit cloud IDE. It builds, runs, and deploys applications inside Replit's Nix-based, Linux containerized environment. As of the 2026 crawl it natively supports three of the six gald3r-relevant primitives — Agent Skills (SKILL.md in /.agents/skills, the agentskills.io open standard), rules/memory (the replit.md instruction file), and MCP (Agent is a first-class MCP client and Replit ships a hosted MCP server). Agents are partial (user-selectable Plan/Build modes + effort tiers are native, but there is no documented user-definable custom-agent file format). Hooks and commands are not supported — there is no lifecycle-hook config and no user-authored slash-command registry (Workflows are adjacent shell-command runners, not an agent command surface).

Authoring path: UPDATE. Verified 2026-06-02 against https://docs.replit.com (see Verification Evidence). This supersedes the prior spec (last_doc_scan: never/2026-05-20), which incorrectly marked skills as unsupported and agents as a hard ❌ — Agent Skills shipped (~April 2026) and are NATIVE, and Plan/Build modes + effort tiers make agents an honest ⚠️ partial.

Instruction-file convention: Replit standardizes on replit.md (project root), NOT AGENTS.md/CLAUDE.md. Replit's own docs say "Agent automatically reads your replit.md file" and it "must be located in your project's root directory to work properly." AGENTS.md appears only in unofficial community blogs; treat replit.md as the canonical surface.

Surface split: the on-disk, versioned gald3r surface is Agent Skills (/.agents/skills) + replit.md. MCP and the OAuth Integrations connectors live in the cloud UI (not a committed file). Modes/effort tiers are interactive UI controls. Hooks/commands have no surface at all. Where a feature is UI-only or cloud-constrained it is noted inline.


1. Folder Hierarchy

Replit is cloud-IDE-first. The only on-disk surfaces relevant to Replit + gald3r are:

<repl-root>/
├── replit.md                     ← Agent custom instructions + persistent memory (auto-created,
│                                   auto-read on every request, Agent may self-update it). PRIMARY
│                                   gald3r instruction surface — NOT AGENTS.md/CLAUDE.md.
├── .agents/
│   └── skills/  <name>/SKILL.md   ← Agent Skills (agentskills.io open standard; Project scope,
│                                   versioned in the repo). NATIVE, lazy-loaded by name+description.
├── .replit                       ← Repl config (TOML): run command, language, entrypoint, [nix], [deployment]
├── replit.nix                    ← Nix environment definition (system packages / toolchain)
└── .gald3r/                      ← gald3r project state (works on disk in the container; commit often — §8 caveats)
  • gald3r writes: replit.md (task conventions + pointers); /.agents/skills/<name>/SKILL.md (the gald3r skill tree — this is now a real native load path); the .gald3r/ state tree.
  • Replit owns: the cloud IDE, the Nix container lifecycle, the .replit/replit.nix schemas, the Integrations + MCP panes (cloud UI), and the Agent runtime (modes/effort tiers). .replit/replit.nix are environment/run config, not AI-instruction files.

Skills also have User and Enterprise scopes (account/org level), and the picker discovers extra skills in .local/secondary_skills/. Only the Project scope (/.agents/skills) is the committed, gald3r-shippable surface.


2. AI Instruction File — ✅ NATIVE (replit.md)

Replit Agent reads replit.md (repl root) as its Custom Agent Instructions + project memory:

  • Auto-created on first Agent use; auto-read into context on every request to understand project architecture, conventions, preferred package managers, and coding style.
  • Self-updating: "Agent can also update your replit.md file as it learns more about your project" — so injected gald3r conventions can be overwritten unless re-asserted (durability caveat). Replit also describes decision-time injection of guidance for reliability.
  • Root-only: must sit at the project root to work; Replit-scoped — "doesn't automatically apply to other AI tools."
  • AGENTS.md is NOT the official convention — it appears only in community blogs; Replit's docs standardize on replit.md.
  • Source: https://docs.replit.com/replitai/replit-dot-md

gald3r merges task-management conventions into replit.md: task IDs in commits (feat(T{id}): …), "tasks live in .gald3r/TASKS.md", "read .gald3r/CONSTRAINTS.md before architecture changes", "read .gald3r/learned-facts.md for durable facts". Re-prime at session start (Agent rewrites it).

3. Agents Support — ⚠️ PARTIAL

  • Native, user-selectable: Plan mode ("brainstorm … before Agent changes any code or data") vs Build mode, plus effort/cost tiers (Lite / Economy / Power / Turbo). These are first-class user controls over agent behavior.
  • Internal orchestration only: specialized subagent ROLES (manager, editor, verifier) and parallel subagents exist, but are described in Replit's blog/case studies as internal orchestration — NOT a user-definable custom-agent/role file format. Agent 3 "Stacks" (create specialized agents/automations) is emerging but not documented as a config primitive on docs.replit.com.
  • gald3r mapping: g-agnt-*.md files have no native file load path. Express agent roles as prose in replit.md, or (better) as Agent Skills (§4). Use Plan mode for review/verify gates.
  • Source: https://docs.replit.com/replitai/agent

4. Skills Support — ✅ NATIVE

  • Agent Skills (agentskills.io SKILL.md open standard): "Skills live in your project's /.agents/skills directory and conform to the Agent Skills specification — an open standard that works across agents." "A skill is a Markdown file containing instructions Agent follows."
  • Lazy-loaded: "Agent sees the name and description of every installed skill, but only loads the full content when relevant." Invoked via the "Use a skill" picker.
  • Scopes: Project (versioned in /.agents/skills), User, Enterprise. Agent can self-author a skill from a successful session ("ask Agent to capture what it learned"); the picker also discovers .local/secondary_skills/. Added ~April 2026.
  • gald3r mapping: g-skl-*/SKILL.md load natively from /.agents/skills/ — this is the primary gald3r delivery surface on Replit (a real reversal from the prior ❌).
  • Source: https://docs.replit.com/replitai/skills

5. Commands / Workflows — ❌ NOT SUPPORTED (as agent commands)

  • No user-authored agent slash-command registry. Official docs document no /command authoring for the Agent — there is no .cursor/commands/g-*.md analogue and no @g-* invocation surface.
  • Workflows are the closest native feature: "an easily configurable Run button that can run any command(s) you'd like." These are shell-command runners (build/test/run pipelines), not reusable agent-prompt commands — adoptable as a gald3r build/test runner only.
  • gald3r mapping: gald3r g-* commands are not executable as commands. A user triggers a gald3r workflow by invoking the matching Agent Skill (§4) or describing intent in chat.
  • Source: https://blog.replit.com/introducing-workflows

6. Hooks System — ❌ NOT SUPPORTED

  • No user-scriptable lifecycle hooks. Replit documents an Agent task lifecycle (planned → running → ready → finished) but exposes no user-defined event/lifecycle hooks that run a script — no session-start, pre-tool, pre-commit, or file-watch hook authoring. Git-workflow hooks are an open community feature request, not a shipped feature.
  • Compounding constraint: the container is Linux — even if hooks could be wired, gald3r's g-hk-*.py scripts need a python interpreter on the container (availability in a standard Replit Nix container is unverified; no PowerShell dependency post- Python port).
  • gald3r mapping: session-start context injection, agent-complete, pre-commit, and shell-guard hooks must be replaced by replit.md prose (e.g. "before completing a task, re-read CONSTRAINTS.md") or git core.hooksPath bash scripts — not enforced gald3r code.
  • Source: https://docs.replit.com/references/agent/task-lifecycle

7. Rules / Memory — ✅ NATIVE (replit.md)

  • Mechanism: replit.md is the persistent, always-on instructions/memory surface — "Agent automatically reads your replit.md file and uses its contents to understand your project's architecture and conventions [and] follow your preferred coding patterns and style."
  • No granular scoping: there is no .mdc extension, no alwaysApply:/globs: frontmatter, and no per-file rule auto-load like .cursor/rules/. gald3r rules (g-rl-*.md) collapse into a single replit.md instruction blob (all-or-nothing context injection).
  • Durability caveat: because Agent self-updates replit.md, injected gald3r rules can be rewritten or trimmed over a session. .gald3r/learned-facts.md remains the authoritative fact store, but Agent won't auto-read it unless replit.md points there.
  • Source: https://docs.replit.com/replitai/replit-dot-md

8. MCP Support — ✅ NATIVE

  • Client: Replit Agent is an MCP client — "An MCP client is something like Claude, Replit Agent, or a command-line interface…"; users "connect a pre-listed MCP server or add a custom one in Replit." Servers are added through the cloud UI (Integrations / Connect-via-MCP), not a committed mcp.json; tools are auto-discovered.
  • Server: Replit also ships a hosted MCP server — "Replit's MCP server lets external clients create, update, and manage full-stack applications on Replit" (e.g. claude mcp add --transport http replit https://replit-mcp.com/server/mcp), with OAuth consent on first connect. This enables external orchestration of Replit projects from another gald3r host.
  • gald3r mapping: add the gald3r MCP server as a custom MCP server in the UI. The endpoint must be a reachable remote URL (the container cannot reach a different machine's localhost), stored as a Replit Secret. This is the strongest gald3r integration surface on Replit.
  • Source: https://docs.replit.com/learn/model-context-protocol

Parity vs. Cursor Reference

Replit reaches partial parity with the Cursor reference (g-skl-platform-cursor): native skills, rules, and MCP; partial agents (Plan/Build modes + effort tiers, no custom-agent files); and no hooks or commands. The big change from the prior assessment is Agent Skills — gald3r's g-skl-*/SKILL.md tree now has a real native load path at /.agents/skills/.

Reuse note: ship the gald3r skill tree into /.agents/skills/ (agentskills.io standard, Project scope, versioned in the repo) and point replit.md at .gald3r/ conventions. There is no hook/command surface, so degrade those gald3r layers to replit.md prose + Workflows (build/test) + Plan mode (review gate). Native bonus: OAuth Integrations connectors (Notion, Dropbox, Stripe, etc.) distinct from generic MCP.

Hook System

  • Type: none
  • Config file: n/a (no lifecycle-hook config; no settings hook wiring for Agent)
  • Events available: none — no session-start / pre-tool / pre-commit / file-watch. The only lifecycle surface is the Agent task lifecycle (planned → running → ready → finished), which is observational, not a script-execution hook
  • Event payload format: none
  • Limitations: container is Linux — even if wired, g-hk-*.py scripts need a python interpreter on the container (availability unverified; no PowerShell dependency post- port); container restarts reset uncommitted state. Git-workflow hooks are an open community request, not shipped
  • gald3r hook files: none auto-fire — hook behaviors must run via replit.md prose, git core.hooksPath bash scripts, or manual invocation

Atypical Handling

  • Cloud Linux container: gald3r .py hooks need a python interpreter on the container (availability unverified; no PowerShell dependency post- port).
  • Instruction file is replit.md (auto-created, auto-read, self-updated) — not AGENTS.md/CLAUDE.md.
  • Skills load from /.agents/skills/ (agentskills.io standard) — a real native surface.
  • MCP/Integrations live in the cloud UI (not committed files); the gald3r MCP endpoint must be a reachable remote URL (no cross-machine localhost), stored as a Replit Secret.
  • Container restarts reset uncommitted state — commit .gald3r/ files frequently.

gald3r Integration Notes

  • Ship gald3r skills to /.agents/skills/ — Replit Agent discovers them natively (lazy-loaded).
  • Put task conventions + .gald3r/ pointers in replit.md; re-prime at session start (Agent rewrites it).
  • gald3r hooks (.py, C-NO-PS1) do NOT auto-fire on Replit — no lifecycle hook system exists here; treat hook automation as unavailable; express behaviors in replit.md or git core.hooksPath bash.
  • Use Plan mode as the review/verify gate; Workflows as the build/test runner.
  • Re-verify on the next @g-platform-scan-docs replit (crawl_max_age_days: 14).

Capability Summary

Hooks Rules Skills Commands MCP Docs Fresh

Legend: ✅ verified working · ⚠️ partial / Cursor-generic · ❌ not supported · ❓ untested.


Verification Evidence (docs crawl 2026-06-02, https://docs.replit.com)

Capability How verified
Instruction file (replit.md) /replitai/replit-dot-md — "Agent automatically reads your replit.md file"; "must be located in your project's root directory to work properly"; Agent can self-update it. NOT AGENTS.md/CLAUDE.md (community-only)
Rules / memory /replitai/replit-dot-md — replit.md is the always-on instructions/memory blob; no .mdc, no alwaysApply:/globs: scoping
Skills /replitai/skills — agentskills.io SKILL.md in /.agents/skills; lazy-loaded by name+description; Project/User/Enterprise scopes; "Use a skill" picker; ~April 2026
Agents /replitai/agent — native Plan/Build modes + effort tiers (Lite/Economy/Power/Turbo); subagent roles are internal orchestration, not a user-definable file format; Agent 3 "Stacks" undocumented as config
Commands / Workflows blog.replit.com/introducing-workflows — Workflows = "Run button that can run any command(s)" (shell runners), not agent slash-commands; no /command authoring documented
Hooks /references/agent/task-lifecycle — task lifecycle planned→running→ready→finished documented, but no user-defined script hooks; git hooks are an open community request; no hook surface for gald3r g-hk-*.py to wire into
MCP /learn/model-context-protocol — Agent is an MCP client (connect pre-listed/custom server, auto tool discovery); Replit ships a hosted MCP server (replit-mcp.com, OAuth on first connect) for external orchestration
Cloud constraints Known-platform — Linux Nix container (python interpreter availability unverified), ephemeral state on restart, MCP/Integrations are cloud-UI surfaces, Replit Secrets replace .env
Install / live connection ❓ Not install-tested in this repo; no live Replit Agent run performed

Reference page — canonical source: g-skl-platform-replit/PLATFORM_SPEC.md in the engine repo, generated by scripts/generate_platform_support_docs.py. Pages marked curated are hand-assessed and not yet live-verified.