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Agent Mode

Pluxx has two product layers:
  • Core: deterministic scaffolding, validation, build, install, and sync
  • Agent: guided semantic refinement driven by Claude Code, Codex, or another coding agent
Pluxx does not need to become its own AI orchestration runtime to solve the hard part of plugin authoring. The right split is:
  • let Pluxx own the structure, hard rules, and safe write boundaries
  • let the host agent own the semantic judgment
That matches how people already work. They are inside Claude Code or Codex anyway, so Pluxx should prepare the scaffold and the prompt/context pack that the agent needs to do high-quality refinement.

Why Agent Mode Exists

pluxx init --from-mcp can always produce a valid scaffold from:
  • MCP transport + auth
  • serverInfo
  • tools/list
  • tool descriptions and input schemas
That is enough to build:
  • pluxx.config.ts
  • baseline INSTRUCTIONS.md
  • baseline skills/*/SKILL.md
  • generated hooks / scripts
  • platform bundles
But complex MCPs need more than valid scaffolding. PlayKit is a good example. Raw introspection can discover the tools, but it does not fully recover the product narrative:
  • setup vs runtime tools
  • knowledge tools vs API tools
  • account/usage/admin surfaces
  • the way the product is actually explained on its site and docs
That is where Agent Mode comes in.

Product Definition

Core Mode

Core Mode stays deterministic and model-free. It owns:
  • MCP introspection
  • config generation
  • baseline skill generation
  • lint
  • build
  • install
  • sync
  • file ownership rules

Agent Mode

Agent Mode prepares the semantic context and prompt pack for the host agent. It owns:
  • MCP summary for the agent
  • product/workflow context
  • prompt packs for taxonomy, instructions, and review
  • explicit write boundaries
  • acceptance criteria for the refinement pass
It does not own model execution.

User Flow

Flow A: Core only

Use this when a deterministic first pass is enough.

Flow B: Core + Agent

Then in Claude Code or Codex:
That is the intended semantic-authoring flow.

Commands

Phase 1 should support:
--attach is only supported for the opencode runner. Autopilot mode defaults:
  • quick: keep the run near-deterministic unless metadata warnings force a taxonomy cleanup pass
  • standard: the default; only invoke expensive passes when metadata quality or extra docs/context suggest they will help
  • thorough: always run taxonomy and instructions, and include review by default
Optional flags:
Provider modes:
  • auto: use Firecrawl when configured and fall back to the local OSS path when not
  • firecrawl: require Firecrawl-backed scraping
  • local: force local fetch + extraction

Runner Adapters

Agent Mode is file-first. The runner layer is optional. pluxx agent run does three things:
  1. refreshes .pluxx/agent/context.md and .pluxx/agent/plan.json
  2. refreshes the selected prompt pack (and after a successful taxonomy run, refreshes all prompt packs so saved packs stay aligned with renamed/merged skills)
  3. invokes a host agent in headless mode against those files
Current built-in runners:
  • claude
  • cursor
  • opencode
  • codex
If you want the entire deterministic + agent flow in one command, use pluxx autopilot. It composes scaffold import, agent refinement, and final verification without introducing a separate authoring engine.

Verification Contract

For edit-oriented runs like taxonomy and instructions, Pluxx verifies the scaffold after the host agent exits by running the normal Pluxx verification flow. For read-only runs like review, Pluxx disables verification automatically and keeps the host runner in read-only/review mode where supported. Deterministic scaffold rewrites (pluxx sync --from-mcp or taxonomy re-renders) invalidate saved .pluxx/agent/* pack files. Regenerate them with pluxx agent prepare/pluxx agent prompt (or run pluxx agent run / pluxx autopilot, which refreshes them automatically).

Generated Files

pluxx agent prepare generates:
If you pass a specific docs page like https://docs.firecrawl.dev/mcp-server, Pluxx uses that page directly and also infers the broader docs root when it can. That gives Agent Mode both the MCP-specific setup page and the higher-level product docs context. When remote sources are present, .pluxx/sources.json now records the requested and resolved ingestion provider so the provenance trail stays inspectable. Prompt packs are generated separately:
Project-owned overrides live outside the generated .pluxx/agent/ directory:
Use that file for durable Agent Mode customization. The generated prompt packs are disposable. Example:

context.md

The semantic handoff for the host agent. Should include:
  • MCP identity and auth summary
  • discovered tool inventory
  • current generated skills and their tool assignments
  • optional docs/site summary
  • known caveats from lint/test
  • the intended output quality bar

plan.json

Machine-readable constraints for the agent. Should include:
  • editable files
  • editable sections
  • non-editable files
  • success criteria
  • known caveats

taxonomy-prompt.md

Prompt for:
  • grouping tools into real product/workflow skills
  • merging/splitting/renaming generated skills
  • identifying setup/admin/account surfaces
  • avoiding misleading labels and unnecessary singleton skills

instructions-prompt.md

Prompt for rewriting the generated block in INSTRUCTIONS.md. It should use branded product wording and avoid raw MCP-internal naming unless technically required.

review-prompt.md

Prompt for evaluating whether the scaffold is actually good after refinement.

Write Boundaries

Agent Mode only works if the write contract is explicit. The host agent may edit:
  • the generated block in INSTRUCTIONS.md
  • the generated block in each skills/*/SKILL.md
  • files under .pluxx/agent/
The host agent must not edit unless explicitly requested:
  • auth wiring in pluxx.config.ts
  • target platform configuration
  • user-owned custom sections
  • generated platform bundles in dist/
  • pluxx.agent.md
This lets agents do meaningful semantic work without turning the scaffold into an unreviewable mess.

Prompt Contract

The prompt packs should be constrained, not vague. Example taxonomy prompt:

Steering Complex MCPs With pluxx.agent.md

For larger MCPs, use project overrides to steer taxonomy and instructions without editing Pluxx internals:
  • ## Grouping Hints: propose durable product-surface buckets (for example onboarding, account-and-usage, runtime-workflows)
  • ## Taxonomy Guidance: call out anti-patterns (misleading labels, one-tool singleton sprawl, setup/admin mixed into runtime)
  • ## Instructions Guidance: force branded language and explicit setup/admin/account/runtime boundaries
This keeps prompt shaping project-owned, durable, and safe across regenerated prompt packs.

PlayKit Example

The deterministic import of PlayKit produced a working scaffold, but the grouping was still mostly lexical. Agent Mode should help move that scaffold toward a more product-shaped taxonomy like:
That is the type of semantic refinement Agent Mode is designed to unlock.

Why Not Built-in Smart Mode

Built-in Smart Mode sounds appealing, but it creates a larger product than Pluxx needs right now:
  • provider abstraction
  • model auth and billing
  • retries and fallbacks
  • nondeterministic support burden
  • prompt/runtime orchestration inside the CLI
Agent Mode avoids that complexity. Pluxx should remain:
  • deterministic in Core
  • agent-native in semantic refinement
If a built-in model layer is ever added later, it should reuse the same context pack and write-boundary model that Agent Mode establishes first.

Phase 1 Scope

Phase 1 Agent Mode should ship:
  • pluxx agent prepare
  • prompt pack generation
  • context pack generation
  • explicit write boundaries
  • docs links from README / docs
It does not need:
  • built-in model execution
  • provider abstraction
  • prompt marketplace complexity
  • automatic commit/publish flows

Success Criteria

Agent Mode is successful when:
  • a user can scaffold from an MCP in Core mode
  • run pluxx agent prepare
  • hand the prompt/context pack to Claude Code or Codex
  • get a better plugin without losing deterministic safety
  • preserve custom edits across future syncs

Dogfood Plugin

This repo now ships a repo-local Codex plugin plus marketplace metadata for the local plugin catalog. The dogfood/operator skill pack now centers the main Pluxx jobs:
  • pluxx-import-mcp
  • pluxx-migrate-plugin
  • pluxx-validate-scaffold
  • pluxx-refine-taxonomy
  • pluxx-rewrite-instructions
  • pluxx-review-scaffold
  • pluxx-build-install
  • pluxx-sync-mcp
Use it to drive the same Core + Agent workflow from inside Codex instead of remembering raw commands.