Mimic Baseline Training Boundary

Summary

This document defines the future training line for computer-use-mcp.

The current decision is deliberately conservative:

• Do not start full VLA or embodied model training now.
• Do not wire any learned model into runtime execution now.
• Do not mix this line with chafa, CLI, desktop UI pet work, or terminal coding workflows.
• Start with a bounded mimic baseline / learned candidate scorer experiment.

The learned component should eventually rank low-level UI candidates or actions. It must not understand user language, execute tools, bypass approval, or decide that a task is complete.

Status

Current status: experiment boundary only.

This package does not currently contain a trained computer-use model. Any future mimic scorer is advisory data until explicit runtime integration, approval, and verification contracts are written and tested.

Architecture Boundary

The intended division of responsibility is:

• LLM / planner handles language understanding and decomposes the user goal into a structured current subgoal.
• Observer provides screenshot, DOM / AX tree, candidate elements, current URL/title/state, and previous action trace.
• Mimic policy performs only observation -> candidate/action ranking.
• Runtime gate, approval discipline, action executor, and verification gate decide whether anything can execute.

Authority order:

runtime/system rules
active user instruction
approval and safety policy
verification gate
trusted current-run tool evidence
planner subgoal / plan state
observer candidate set
mimic scorer ranking
model guess

The mimic scorer can inform selection. It cannot authorize execution.

V1 Experiment Shape

If an experiment folder is created, use:

services/computer-use-mcp/experiments/mimic-baseline/

Possible files:

trace-schema.ts
collect-trace.ts
build-dataset.ts
eval-candidate-scorer.ts
README.md

V1 scope:

1. Define a trace schema.
2. Define observation, candidate, and action data structures.
3. Build a trace collector for deterministic browser/macOS UI tasks.
4. Save task goal, current subgoal, screenshot, DOM / AX candidates, previous actions, human-chosen next action, and expected effect / verification result when available.
5. Map human click/type/scroll actions back to candidate IDs.
6. Build a dataset builder.
7. Build an offline eval script.

Do not implement training before this substrate exists.

Trace Schema V1 Sketch

The first schema should be append-only friendly and deterministic.

interface MimicTraceRecordV1 {
  schema: 'computer-use-mcp.mimic-trace.v1'
  traceId: string
  stepId: string
  createdAt: string

  taskGoal: string
  currentSubgoal: string

  observation: {
    screenshotPath?: string
    screenshotSha256?: string
    url?: string
    title?: string
    app?: string
    windowTitle?: string
    candidates: MimicCandidateV1[]
  }

  previousActions: MimicActionV1[]
  chosenAction: MimicActionV1
  chosenCandidateId?: string
  mapping: {
    status: 'matched_candidate' | 'no_target' | 'ambiguous' | 'outside_observed_bounds'
    candidateId?: string
    distancePx?: number
    reason?: string
  }

  expectedEffect?: string
  verification?: {
    status: 'passed' | 'failed' | 'unknown'
    summary?: string
  }

  source: {
    collector: 'manual' | 'deterministic_demo' | 'human_replay'
    platform: 'macos'
    browser?: 'chrome'
  }
}

Candidate and action structures should stay low-level:

interface MimicCandidateV1 {
  id: string
  source: 'chrome_dom' | 'ax' | 'vision' | 'manual'
  role?: string
  label?: string
  text?: string
  bounds: { x: number, y: number, width: number, height: number }
  enabled?: boolean
  visible?: boolean
  metadata?: Record<string, unknown>
}

type MimicActionType = 'click' | 'type_text' | 'scroll' | 'press_key' | 'wait' | 'no_target'

interface MimicActionV1 {
  type: MimicActionType
  candidateId?: string
  point?: { x: number, y: number }
  text?: string
  direction?: 'up' | 'down' | 'left' | 'right'
  key?: string
}

Do not put raw secrets, cookies, API keys, or full browser storage into traces.

Dataset Builder Contract

The dataset builder should convert trace records into bounded examples:

input:
  task goal
  current subgoal
  screenshot reference
  candidate list
  previous actions

label:
  chosen action type
  chosen candidate id when mapped
  no-target / unmapped status when not mapped

The first dataset format can be JSONL. It should keep screenshots as referenced files, not inline base64, unless a later training backend requires packaging.

Offline Eval Metrics

The first offline eval script should report:

• Top-1 candidate match
• Top-3 candidate match
• action type accuracy
• no-target / unmapped-action rate
• unsafe / invalid candidate rate if applicable

Eval output should be deterministic and file-based. It should not call a runtime tool, mutate the desktop, or require a model provider key for the first schema contract.

Promotion Gates

Do not discuss runtime integration until all of these are true:

• at least 50 to 100 clean traces exist
• candidate extraction is stable for the target demo tasks
• human action mapping has an explainable low unmapped rate
• offline top-k metrics are repeatable
• unsafe / invalid candidate cases are measured, not hand-waved
• approval and verification boundaries remain unchanged

Even after those gates pass, a learned scorer must enter runtime as advisory ranking only. It must not execute tools directly.

Chika Ownership Boundary

Chika may own these bounded experiment tasks:

• collector
• schema
• deterministic browser demo task
• candidate mapping
• dataset builder
• offline eval

Chika should not own these in the first slice:

• full VLA training
• runtime execution integration
• Windows support
• terminal coding workflow integration
• model deployment
• product claims that AIRI has a trained computer-use model

Non-Goals

• No full VLA training.
• No runtime auto-execution.
• No terminal coding workflow.
• No Windows support.
• No model deployment.
• No MCP schema changes unless strictly necessary for trace serialization.
• No desktop/chafa/CLI pet integration.
• No product claim that AIRI has a trained computer-use model.

Reminder Trigger

When this line is reopened, remind the owner of the current decision:

Do not train or deploy yet. First prove the mimic trace schema, deterministic
collector, candidate mapping, dataset builder, and offline eval.

Revisit the training decision only after the promotion gates above are met.