One host · independent reviewers · explicit authority

Independent review for coding agents.

One product. Two workflows. A Multi-agent system: independent model advisors inspect one host task, while Codex or Claude Code remains the editor and integrator. that keeps one host responsible.

Start with a one-shot consultation for research, planning, or review. Opt into Panda Loop v2 only when the task needs evidence-gated readiness, bounded repair, and a durable decision record.

Product map

Choose the authority you need

Panda 2.0 is the current product release, not a third workflow. Panda has one shared reviewer profile and two distinct operating modes.

Product Panda 2.0

Install once. Select a workflow per task.

Release notes
Default · advisory 01

Panda Consultation

Ask independent reviewers to inspect a plan, diff, or difficult engineering question. The host synthesizes the advice and remains responsible for every decision.

Use when
Research, planning, second opinions, or implementation review
Output
Structured advisory findings and evidence sidecars
Authority
No readiness claim and no mutation authority
Explore consultation
Optional · evidence-gated 02

Panda Loop v2

Bind a task and workspace, run verifiers, require every reviewer gate, and allow repair only inside explicit limits.

Use when
Verification, readiness decisions, or bounded repair
Output
Host-derived ready, repair_required, or escalate
Authority
Read-only review; explicit, limited Codex repair
Explore Loop v2
Shared invariant

Independent reviewers inspect. The host integrates. Consultation advises; Loop derives decisions from host evidence.

Shared setup

One installation, both workflows

Consultation and Loop v2 use the same plugin installation and saved reviewer profile. Choose the workflow per task; do not install a second Panda.

Host install request
You

Please install Panda as Codex and Claude Code plugins. Use the latest release: https://github.com/igcodinap/panda/releases/latest From the Panda checkout: python3.12 -m pip install -e '.[mcp]' codex plugin marketplace add /path/to/panda codex plugin add panda@panda-repo claude plugin marketplace add /path/to/panda claude plugin install panda@panda-repo Verify both plugin managers list panda@panda-repo as enabled.

Host

I’ll install the MCP extra, add the Panda marketplaces, install the Codex and Claude Code plugins, and verify both are enabled.

Codex plugin codex plugin marketplace add /path/to/panda codex plugin add panda@panda-repo
Claude Code plugin claude plugin marketplace add /path/to/panda claude plugin install panda@panda-repo
Requirements
  • Python 3.10+ for plugin MCP
  • Codex CLI installed and authenticated for Codex-hosted runs or Codex reviewer runs, or CODEX_BIN set to an authenticated CLI
  • Claude Code optional, as a Claude Code host via --host-profile claude-code or for Claude-backed advisors
  • OpenCode optional, for Kimi, GLM, Qwen, or other OpenCode-backed advisors

The minimum working setup is Python plus one host CLI. Codex is the default host/reviewer path; Claude Code uses the claude-code host profile. OpenCode remains an optional source of extra review pressure.

ROI recommendation: after your host CLI, the first optional paid add-on is OpenCode Go, currently listed at $5 for the first month and then $10/month. It gives Panda a separate budget for Kimi, GLM, Qwen, and other OpenCode-backed review agents.

Default workflow · advisory

Panda Consultation

Independent reviewers inspect a question, plan, or implementation. The host synthesizes their advice; consultation never claims the workspace is ready and never authorizes mutation.

Host advisory consultation
You

Review this implementation plan with Panda.

Host

Using Panda to analyze the research and plan. I will integrate the useful findings.

default reviewer With no saved profile, Panda starts one Codex reviewer: gpt-5.5 at medium reasoning.
profile file shared by both workflows: ~/.config/panda/preferences.json
authority reviewers advise · host integrates
Where consultation helps

Apply review pressure before and after coding

Panda focuses on research and plan quality before implementation, then checks the result for drift, missing tests, and inconsistencies.

Panda focuses review pressure where coding agents have the most leverage A leverage map showing Panda focusing on research and plan quality before the host implements, then checking the finished diff against the research, plan, and tests. highest leverage is upstream Research and plan quality shape every later token. Panda pressure zone research facts • constraints plan approach • tests implementation host writes the diff after coding: consistency check does the diff still match the research, plan, and tests? wrong research → wrong problem weak plan → wrong solution
highest leverage Research and plan

Panda spends extra model attention before the host writes code, where a wrong read or weak plan can cascade into much larger implementation waste.

after coding Check the implementation

Once the host implements, Panda can review the diff against the research and plan to catch drift, inconsistencies, and verification gaps.

Optional workflow · evidence-gated

Panda Loop v2

Loop is the strict execution workflow: bind the task and workspace, verify, require every reviewer gate, and repair only within explicit authority. It is not the default consultation path.

Technical controls Evidence, falsification, and bounded repair Expand the strict policies and stop conditions. Missing evidence always escalates.
01 · contract

Preflight turns plans into guardrails

panda_loop.py preflight hashes the normalized task, freezes the reviewer profile, runs deterministic guardrail checks, and asks Panda to critique only the instruction boundary.

  • Flags broad goals, weak verifiers, missing non-goals, unsafe commands, and loose stop rules.
  • Writes authoritative panda_preflight.v2.json for later enforcement.
  • Writes advisory contract_coach metadata to score the task setup.
  • Chat agents show a Loop Contract Preview before any state-changing run.
  • Any grooming after preview requires fresh preflight and fresh execution approval.
  • run --require-preflight fails if any task, reviewer, workspace, artifact, repair, or mutation input drifts.
02 · decision gate

Evidence drives readiness

The loop fingerprints the workspace, records sanitized verifier evidence, and requires every frozen reviewer to return an evidence-addressable gate from a read-only role.

  • Ready requires green verifiers, valid coverage, an unchanged reviewed workspace, and no blockers.
  • Empty, malformed, abstaining, timed-out, or incomplete reviews escalate.
  • Summary mode exports no raw source, diffs, or logs and requires a pinned implementation summary.
03 · optional antagonist

Falsification stays advisory

The default-off falsifier opens a fresh one-shot session, prefers a different model family, and classifies every registered claim exactly once. A source model cannot adjudicate its own claim.

  • Contradictions require counter-evidence and mark claims disputed.
  • not_found requires a recorded search scope.
  • A falsifier may escalate; it never authorizes readiness or repair.
04 · bounded execution

Bounded repair and recovery

Automatic repair and typed repair_steps require a structured report and stay inside path, file, line, binary, symlink, cycle, repair, and wall-clock limits. The next evidence cycle proves the result.

  • Automatic repair uses Codex workspace-write; reviewer backends stay read-only.
  • Review-only blockers escalate unless repair authority is explicit.
  • Legacy string repair commands still run, but reportless summary-mode mutation escalates.
  • No-op, repeated, oscillating, drifting, or over-limit repair stops.
  • inspect, safe resume, and workspace-safe abort preserve control.
Workflow

How Loop v2 works

Shape the task, preflight it, execute only the approved preview, then let verification and independent review derive ready, repair_required, or escalate.

Flow map What moves, who owns it, and where the loop can stop
required gate repeat done
01

Contract before execution

Developer Names the target and boundaries

Objective, non-goals, verifiers, repair budget, and mutation limits.

Host agent Creates or tightens task.json

Uses repo context but does not edit product code yet.

Panda No reviewer fan-out yet

Preflight is the next authority boundary.

Artifact task.json

Schema v2 is hashed with the exact execution policy.

required
02

Preflight and preview

Developer Reads the preview

Looks for scope creep, weak tests, unsafe repair, or missing stop rules.

Host agent Runs panda_loop.py preflight

Shows findings and the Loop Contract Preview before execution.

Panda Scores the contract

Reviewer failures and review-time workspace drift block approval.

Artifact panda_preflight.v2.json

Binds task, reviewers, workspace, evidence, repair, and mutation policy.

gate
Preview approved?

No means groom the contract and rerun preflight. Yes means execute the exact preview with --require-preflight.

03

Gated execution loop

Developer Stays out unless blocked

Intervenes on ambiguity, unsafe commands, or changed intent.

Host agent Verifies, repairs, and reports

Edits only through a bounded implementer and validates its repair report.

Panda Runs independent review

Every reviewer must cover registered evidence; the falsifier stays advisory.

Artifact panda_review_gate.v1.json

Iteration evidence and replayable events bind the decision to the workspace.

repeat
All evidence gates valid?

Ready requires green verifiers, every reviewer, sufficient coverage, stable fingerprints, and no critical or major finding.

04

Ready state

Developer Gets the decision record

Sees terminal status, decision reasons, blockers, and the evidence artifact path.

Host agent Hands off the exact green state

No silent follow-up edit after readiness without another evidence cycle.

Panda Stops advising

The host remains the sole editor and integrator.

Artifact loop_summary.md

The compact summary records status, reasons, blockers, and the Panda review artifact directory.

done
Run it

Configure Loop v2

Pin the evidence, approve the preflight preview, then run the exact approved contract.

task.json
{
  "schema_version": 2,
  "objective": "Implement the requested change and keep tests passing.",
  "non_goals": ["Do not refactor unrelated modules."],
  "plan_reminders": ["Preserve public behavior unless the task says otherwise."],
  "verification_commands": ["python3 -m pytest -q -p no:rerunfailures"],
  "implementation_summary_artifact": {
    "path": "implementation-summary.json",
    "sha256": "0000000000000000000000000000000000000000000000000000000000000000",
    "provenance_mode": "scratch"
  },
  "auto_repair": {
    "enabled": true,
    "backend": "codex",
    "allow_review_only_findings": false
  },
  "falsifier": {
    "mode": "off",
    "max_runs_per_evidence": 1
  },
  "mutation_policy": {
    "allowed_paths": ["src/", "tests/"],
    "max_changed_files": 20,
    "max_changed_lines": 1000,
    "allow_binary_changes": false,
    "allow_symlink_changes": false
  },
  "stop_when": {
    "max_verification_cycles": 2,
    "max_repairs": 1,
    "max_wall_seconds": 3600,
    "blocking_findings": ["critical", "major"]
  }
}
preflight
python3 scripts/panda_loop.py preflight \
  --task-file task.json \
  --workspace "$PWD" \
  --privacy-mode advisory-summary \
  --output-dir /tmp/panda-preflight
run with gate
python3 scripts/panda_loop.py run \
  --task-file task.json \
  --workspace "$PWD" \
  --require-preflight /tmp/panda-preflight/panda_preflight.v2.json \
  --privacy-mode advisory-summary \
  --output-dir /tmp/panda-loop
durability controls
python3 scripts/panda_loop.py inspect --output-dir /tmp/panda-loop
python3 scripts/panda_loop.py resume --output-dir /tmp/panda-loop
python3 scripts/panda_loop.py abort --output-dir /tmp/panda-loop --reason user_requested
typed repair task fragment
"repair_steps": [
  {
    "command": "python3 scripts/regenerate_clients.py",
    "report_artifact": "tmp/panda-repair-report.json"
  }
]

This is a policy template. Before advisory-summary preflight, create a valid implementation-summary.json and replace the all-zero placeholder with the raw file's SHA-256. Follow the summary evidence schema; use full-context only when repository export is explicitly approved. Resume acquires the loop lock, rejects task/profile/workspace drift, and never replays an ambiguous interrupted repair.

  1. preflight v2
  2. iteration evidence
  3. review gate
  4. optional falsifier
  5. repair report
  6. events + decision digest

Artifact suffixes identify contract schema versions. A current file such as panda_review_gate.v1.json is part of Loop v2; it does not mean “Loop v1.”

Contract Coach sweet spot

A strong loop task has focused scope, explicit boundaries, meaningful verifiers, bounded repair, tight stop rules, clear privacy posture, and maintainability pressure.

objective scope boundaries verifier coverage repair safety stop rules privacy maintainability
Host Loop v2 request
You

Use Panda Loop v2 for this change. Draft a narrow task contract first: - objective - non_goals - constraints - plan_reminders - verification_commands - implementation_summary_artifact when using advisory-summary - falsifier policy - mutation_policy - stop_when.max_verification_cycles, max_repairs, and max_wall_seconds Run preflight and show me the Loop Contract Preview. Use Contract Coach to tighten weak task boundaries. Do not execute the loop until I approve the current preview. After execution, report tests, reviewer status, artifacts, and commit state.

Loop 1.x upgrade history

Version history Upgrading from Loop 1.x Open this only for legacy Loop tasks, preflight approvals, or event logs.

Core Panda consultation is not obsolete. This migration applies only to strict Loop execution authority: old inputs remain readable, but Loop v2 requires fresh workspace evidence before approval or resume.

Strict boundary

Keep readable history. Rebuild execution authority.

Loop v2 keeps compatibility at the parser and inspection layers while refusing to infer trust from old approvals, partial evidence, or ambiguous side effects.

Task files Legacy and unspecified schemas
Still parsed, with strict normalization

max_iterations aliases verification cycles; conflicting values and verification_passes: false are rejected.

Approval panda_preflight.v1.json
Inspect only; regenerate Loop v2 preflight

Preflight v2 binds the exact task, reviewers, privacy mode, canonical workspace, initial fingerprint, artifacts, repair policy, and mutation limits.

Summary review Advisory prose
Pin structured evidence

advisory-summary needs a valid implementation summary and raw-file SHA-256. Full-context review needs inspected files unless the candidate explicitly made no change.

Reviewer policy Best-effort reviewer gate
Every frozen reviewer is mandatory

There is no quorum fallback. Missing, malformed, abstaining, timed-out, incomplete, or workspace-mutating review escalates.

Repair Broad feedback input
Verifier-backed by default

Review-only repair is opt-in. Automatic and typed repairs produce reports; mutation defaults to 20 files, 1,000 lines, and no binary or symlink changes.

Run history Schema-v1 event logs
Inspectable, never auto-resumed

New runs record phase input digests and idempotency keys. Resume continues only from safe boundaries; ambiguous interrupted repair escalates.

Defaults: without repair, one verification cycle and zero repairs; with repair, two cycles and one repair. Hard ceilings are three cycles, two repairs, and 3,600 seconds. Allowed mutation paths derive from the validated implementation summary unless the task explicitly narrows or broadens them.

Shared proof

Evidence and limits

Panda's architecture is research-informed, but Panda-specific net benefit remains unproven. The evaluation record and research base constrain both workflows without turning promising experience into a product claim.

Evaluation

Measure safety before claiming lift

False-ready rate is primary; solve-rate lift remains an experimental question.

Immutable attempt records

New experiments append to attempts.jsonl with trial identity, pair and parent links, hashes, base commit, exposure count, tokens, cost, wall time, and tool/test calls.

  • Acceptance comes from parsed evaluator output.
  • Human judgments append separately to semantic_ratings.jsonl.
  • Legacy results remain read-only inputs marked legacy.

Equal-budget experimental arms

Repeated fresh attempts cover both baseline successes and failures across five fixed arms:

  • strong_single_agent and fresh_clean_retry
  • panda_v2 and evidence_gated_falsifier
  • full_bounded_loop

These code labels are experiment-arm IDs, not separate Panda products.

Audited benchmark evidence

A valid task-audit must align prompt, tests, reference patch, coverage, dataset revision, auditors, and supporting evidence. Unaudited discovery requires an explicit research flag and stays outside causal metrics.

Safety first False-ready rate is primary, with finding precision/recall, false blockers, false repairs, and repair regressions.

Paired efficacy Solve-rate effect uses exact McNemar results and task-clustered bootstrap intervals; passk tracks reliability and blinded stratified ratings report human agreement.

Complete cost Stalls, iterations, latency, tokens, dollars, calls, and validated findings per 1,000 tokens remain visible.

Claim boundary

Panda does not yet claim statistically proven solve-rate lift over Codex or Claude Code alone. The architecture is research-informed; Panda-specific net benefit remains an experimental question.

Research library

Open the evidence by workflow

Panda uses the literature as constraint, not decoration: coordination has cost, budgets matter, external feedback beats intrinsic confidence, and benchmarks require humility.

Research group 01 Consultation architecture 10 sources · coordination, diversity, synthesis, and benchmark limits

Gao et al., Single-agent or Multi-agent Systems? Why Not Both?

Core claim
Single-agent and multi-agent systems have complementary tradeoffs; coordination has real cost.
Panda implication
Panda runs consultation only where independent pressure is likely to pay for itself.
Caveat
It does not prove Panda's exact advisor shape improves coding outcomes.
Source

CooperBench, Why Coding Agents Cannot be Your Teammates Yet

Core claim
Peer coding agents can fail through coordination, commitment, and communication breakdowns.
Panda implication
Panda advisors inspect independently. Codex or Claude Code remains the single editor and integrator.
Caveat
The benchmark studies collaborative coding, not Panda's fan-out advisory pattern.
Source

Rethinking the Value of Multi-Agent Workflow

Core claim
Strong single-agent baselines can match homogeneous multi-agent workflows in many settings.
Panda implication
Panda must earn its use through heterogeneous evidence and useful pressure, not agent count.
Caveat
Codex or Claude Code alone remains the baseline Panda must beat or complement.
Source

Tran and Kiela, Equal Thinking-Token Budgets

Core claim
When reasoning budgets are equalized, single-agent systems can be more information-efficient.
Panda implication
Panda treats cost, latency, and retained context as part of the result.
Caveat
The result is about multi-hop reasoning, not local software consultation.
Source

Kim et al., Towards a Science of Scaling Agent Systems

Core claim
Agent-system scaling depends on task shape and architecture fit.
Panda implication
Panda stays narrow: independent contract pressure, then single-editor integration.
Caveat
Poor task selection can still waste time or amplify noise.
Source

MAST, Why Do Multi-Agent LLM Systems Fail?

Core claim
Multi-agent failures cluster around design, misalignment, and verification categories.
Panda implication
Panda 2.0 sidecars, parse warnings, and falsifier prompts keep failure modes visible.
Caveat
Taxonomy helps expose failure; it does not eliminate it.
Source

Silo-Bench

Core claim
Agents can exchange information yet still fail to synthesize distributed state.
Panda implication
Panda avoids advisor-to-advisor state merging and leaves synthesis to the host plus tests.
Caveat
The synthesis step still depends on evidence quality and verification discipline.
Source

SWE-bench Pro

Core claim
Long-horizon software tasks better stress realistic debugging and integration behavior.
Panda implication
Panda evaluation should focus on tasks where consultation can actually matter.
Caveat
Unaudited tasks are quarantined from causal efficacy summaries until a task-audit artifact is valid.
Source

Terminal-Bench

Core claim
Command-line tasks expose setup recovery, autonomy, and verification quality.
Panda implication
Panda should be judged on evidence usefulness and recovery planning, not only final patches.
Caveat
Current public Panda results are primarily SWE-bench-style summaries.
Source

OpenAI SWE-bench Verified Methodology Note

Core claim
Saturated and contamination-prone coding benchmarks can stop measuring frontier capability.
Panda implication
Panda reports evaluation status cautiously and separates observed experience from proven lift.
Caveat
This is a methodology note, not an academic paper.
Source
Research group 02 Loop mechanics 6 sources · action loops, refinement, terminal interfaces, and test evidence

ReAct: Synergizing Reasoning and Acting in Language Models

Core claim
Useful agents interleave reasoning, actions, and observations instead of producing one isolated answer.
Loop implication
Panda Loop makes observe-decide-act cycles explicit: verify, Panda review, decide, repair, then verify again.
Caveat
ReAct is a general agent pattern; Panda still needs software-specific verifiers and stop rules.
Source

Self-Refine, Iterative Refinement with Self-Feedback

Core claim
Generate-feedback-refine cycles can improve outputs over one-shot generation.
Loop implication
Panda Loop preserves the refinement cycle while replacing pure self-feedback with tests, review artifacts, and explicit policy.
Caveat
Panda does not treat model self-critique as readiness proof.
Source

Reflexion, Language Agents with Verbal Reinforcement Learning

Core claim
Agents can improve across attempts when success and failure signals are converted into reusable verbal feedback.
Loop implication
Loop artifacts, findings, and plan reminders keep prior feedback visible across bounded repair attempts.
Caveat
Panda keeps feedback scoped to the task and bounded by iteration caps.
Source

SWE-agent: Agent-Computer Interfaces Enable Automated Software Engineering

Core claim
Software agents benefit from command-line interaction patterns and interfaces designed for repository work.
Loop implication
Panda Loop separates verifier commands, review artifacts, repair prompts, and state logs instead of hiding them in one prompt.
Caveat
Interface design helps, but readiness still depends on local evidence and tests.
Source

SWE-bench: Can Language Models Resolve Real-World GitHub Issues?

Core claim
Realistic software repair requires repository context, iterative diagnosis, and test-based validation.
Loop implication
Panda Loop treats verifier output and failing tests as first-class loop evidence, not afterthoughts.
Caveat
Benchmark tests can still miss maintainability or hidden contract regressions.
Source

Terminal-Bench: Benchmarking Agents on Hard, Realistic Tasks in Command Line Interfaces

Core claim
Terminal workflows stress multi-step command execution, setup recovery, and verification discipline.
Loop implication
Panda Loop records shell-facing verification, repair, and review artifacts so failures remain inspectable.
Caveat
It is a benchmark methodology signal, not proof that one loop policy is optimal.
Source