pi-jev

September 20, 2026 · View on GitHub

Semantic tool routing and typed decisions for the Pi coding agent powered by TypeSafe Jev (System One).

Features

Semantic Tool Router (jev_find_tools): Automatically searches registered inactive tools and additively activates only the tools needed for the user's specific prompt or workflow.
Skill Discovery (jev_find_skill): Semantically matches and suggests the most relevant specialized agent skills (SKILL.md) for any task without cluttering prompt context.
Typed Judgments (jev_evaluate): Run fast, calibrated System One decisions directly from the agent using Choice, Noul (yes/no probability), and Score primitives.
Dynamic Evaluations (/jev test <prompt>): The active model designs the Jev question schema for a free-form prompt, then Jev evaluates it.
Automatic Mode (opt-in): --jev-auto / PI_JEV_AUTO=1 / /jev auto on routes tools and suggests skills before every prompt. Off by default.
Automatic Model Mode (opt-in): --jev-auto-model / PI_JEV_AUTO_MODEL=1 / /jev auto-model on selects fast, balanced, reasoning, long-context, or vision models per prompt. Off by default.
Tool Call Guard (opt-in): --jev-tool-guard / PI_JEV_TOOL_GUARD=1 / /jev tool-guard on intercepts tool calls with Jev to detect hallucinations and enhance failed results. Off by default.
Jev Compaction (opt-in): --jev-compact / PI_JEV_COMPACT=1 / /jev compact on uses Jev to retain important tool history during /compact, while Pi's normal compaction remains the safe fallback.
Agent Orchestration & Typed Agent: /jev agents <task> dispatches pi-subagents orchestration; register agent: "jev" in workflows for instant sub-second typed judgments without LLM overhead.
Post-Run Gate Check (jev-gate CLI): Fast binary for subagent gate parameters (npx pi-jev-gate -c "criteria"). Checks git diff / output and exits 0 on pass or 1 on fail.
On-Demand & Safe: Runs when called. No unsolicited per-turn API token costs. Fails closed safely: if Jev is unreachable or unconfigured, tool routing does not blindly activate unjudged tools and reports zero confidence on keyword fallbacks.
Cost Clarity: Tool routing (jev_find_tools, /jev auto), skill discovery (jev_find_skill), evaluations (jev_evaluate), Jev subagents (agent: "jev"), and gate checks (pi-jev-gate) consume a Jev System One request. Heuristic fast-paths like /jev auto-model and topology fallback classify locally without spending Jev requests.

Installation

pi install npm:pi-jev

Or install directly from GitHub:

pi install git:github.com/TheoOliveira/pi-jev

Setup

Set your TypeSafe API key via environment variable:

export TYPESAFE_API_KEY=ts_...

Or store it in Pi's secret store file:

mkdir -p ~/.pi/agent/secrets
echo "ts_..." > ~/.pi/agent/secrets/typesafe_api_key

Then check status inside Pi:

/jev status

Automatic Mode

Opt in to run one Jev routing pass before each agent turn (automatic mode costs one Jev request per prompt):

pi --jev-auto            # per-run CLI flag
export PI_JEV_AUTO=1     # persistent via environment

Toggle at runtime with /jev auto on or /jev auto off (no argument flips it). Automatic mode:

activates inactive tools whose usefulness probability clears JEV_THRESHOLD (0.65);
injects matching skill recommendations into the turn;
skips slash commands, empty prompts, and prompts while Jev is unconfigured or already evaluating;
never throws — a Jev failure leaves the turn untouched.

JEV_THRESHOLD (in src/skills.ts) is the one act/reject cutoff: raise it for precision, lower it for recall. Every path — router, tools, /jev skills, auto mode — reads that same constant.

Jev Gate CLI (`pi-jev-gate` / `jev-gate`)

Use pi-jev-gate as a post-run gate check for subagents or CI/CD pipelines. Evaluates git diff, file, or stdin against natural language criteria using Jev System One probability.

Exits 0 if evaluation probability meets threshold ( $\ge 0.70$ by default).
Exits 1 if rejected.
Exits 2 on error (or 0 with --fail-open).

Subagent `gate` Example

Set a child subagent's gate parameter to run pi-jev-gate immediately upon completion:

{
  "agent": "worker",
  "task": "Refactor auth middleware to use jose",
  "gate": "npx pi-jev-gate -c 'Middleware strictly refactored without breaking exports and no new any types' -d -p 0.8"
}

Pipeline / CLI Examples

# Check git diff against acceptance criteria
npx pi-jev-gate -c "All exported functions have TypeScript type annotations" --diff

# Check piped test/linter output
npm test 2>&1 | npx pi-jev-gate -c "Zero test failures and no unhandled promise rejections"

# JSON output with custom threshold
npx pi-jev-gate -c "Documentation updated" -f ./README.md -p 0.85 --json

Typed Jev Subagent (`agent: "jev"`)

Workflow Example

export const meta = { name: "triage_workflow", description: "Classify and route tasks" };

// 1. Instant typed classification with Jev
const triage = await agent("Classify incoming issue", {
  agent: "jev",
  type: "choice",
  criteria: {
    bug: "Bug or regression in existing behavior",
    feature: "New capability request",
    docs: "Documentation or comment update"
  },
  state: args.issueBody
});

// 2. Route dynamically based on System One verdict
if (triage.primaryValue === "bug") {
  await agent("Fix reported bug and add test", { agent: "worker", task: args.issueBody });
}

Agent Orchestration

/jev agents <task> uses Jev System One to analyze task requirements and construct specialized multi-agent workflow scripts executed via pi-subagents:

Implementation tasks: Staged scout (code context) $\rightarrow$ worker (changes) $\rightarrow$ reviewer (standards & tests).
Research tasks: Parallel scout + researcher $\rightarrow$ worker synthesis.
Review / Security tasks: Parallel reviewer + evidence-auditor.
General tasks: worker $\rightarrow$ reviewer.

Execution is asynchronous; completion is reported back into the session. Automatic dispatch is opt-in via --jev-agents / PI_JEV_AGENTS=1 or /jev auto-agents on.

/jev compact on enables Jev-guided compaction. Tool-history entries are evaluated for retention; important paths, errors, constraints, and results stay in the custom summary. User and assistant intent is not rewritten. The feature preserves Pi's firstKeptEntryId boundary and falls back to Pi's built-in summary when Jev is unconfigured, fails, or returns unusable data. It does not silently truncate context.

Automatic Model Mode

Auto-model uses task signals, attached images, and context size to choose the best available model. It respects ctx.scopedModels, skips low-confidence general prompts, and preserves the current model when no compatible option exists. Models that hit quota, rate-limit, timeout, or context-limit errors are temporarily avoided on later prompts; fallback is bounded and never loops. Provider failures do not silently truncate user context.

Commands

/jev status — Shows Jev configuration (and where the API key came from), auto-mode state, session request count, total tokens, and available tool counts.
/jev help — Lists available subcommands.
/jev skills [query] — Discover and rank matching skills in the workspace using Jev.
/jev test [prompt] — With no prompt, runs the fixed connectivity smoke test. With a prompt, the active model designs the Jev questions for that prompt and Jev evaluates them. Also accepts /jev eval and /jev evaluate.
/jev enable — Enables Jev tools in the active session.
/jev disable — Disables Jev tools for the active session.
/jev auto [on|off] — Turns automatic per-prompt tool/skill routing on or off (no argument flips it).
/jev auto-model [on|off] — Turns automatic model selection on or off (no argument flips it).
/jev tool-guard [on|off] — Turns tool call anti-hallucination validation and error guidance on or off.
/jev compact [on|off] — Turns Jev-guided compaction on or off. Run /compact after enabling.
/jev agents <task> — Dispatches the task to pi-subagents, which selects and coordinates available agents.
/jev auto-agents [on|off] — Enables automatic orchestration for complex architecture, refactoring, security, repository-wide, and migration prompts.

Tools Provided

1. `jev_find_tools`

Used by the model to find capabilities that aren't currently loaded into the prompt prefix.

{
  "query": "inspect SQLite database schemas and run queries"
}

2. `jev_find_skill`

Used by the agent to find relevant specialized workflows and instructions for complex tasks.

{
  "query": "build accessible modal component in React"
}

3. `jev_evaluate`

Used for structured decisions, classifications, triage, and scoring.

{
  "state": { "diff": "..." },
  "questions": {
    "is_breaking": {
      "type": "noul",
      "instructions": "Does this change introduce any breaking API changes?"
    }
  }
}

Development & Testing

npm install
npm run typecheck
npm test