Responsibility Pathway Runtime

Govern external actions without losing evidence, recovery, or the human decision point.

Responsibility Pathway Runtime (RPR) is an MIT-licensed Python runtime for applications that need to place an explicit responsibility pathway in front of consequential external actions. It helps a host application preserve actor and authority declarations, execution-attempt continuity, readback evidence, fail-closed ambiguity handling, repair routes, and Human Gate decisions.

Public Alpha — 0.1.0a2
Tag: v0.1.0a2
Freeze ID: RPR-CF-2026-08-02-01
Tested final rehearsal profile: Linux, Python 3.11
The source repository, product site, browser demo, GitHub Prerelease, and PyPI package are public.
RPR is not a legal-responsibility engine, identity provider, secret manager, production gateway, or guarantee of exactly-once effects across arbitrary remote systems.

PyPI · GitHub Prerelease · Product site · Live browser demo · MCP integration · 日本語の入口 · Quick Start · Product documentation · Report an issue

Why RPR

AI agents and automation can execute faster than people can reconstruct what happened. RPR provides a bounded runtime layer where an integrating application can:

• declare actors, authority, and the proposed action;
• evaluate and retain an explicit pathway state;
• bind operations, attempts, and idempotency identity;
• require independent readback before completion;
• stop ambiguous writes as write_status_unknown instead of false success;
• retain Human Gate, repair, resume, reconciliation, and evidence continuity;
• survive restart without silently repeating unresolved effects.

Current MCP support

Published PyPI 0.1.0a2 can govern outbound MCP tool calls made by a host application. The verified public-alpha path includes local subprocess launch, stdio transport, MCP JSON-RPC framing, admitted server and tool bindings, execution-attempt continuity, fail-closed ambiguous outcomes, and optional independent readback.

host application or agent
  -> proposed MCP tool call
  -> actor, authority, Human Gate, and pathway state
  -> admitted MCP server and tool binding
  -> tools/call
  -> tool result
  -> independent readback when required
  -> completed | write_status_unknown | repair | reconcile | human gate

A successful MCP response is not automatically proof of a consequential external effect. When required readback is missing or a transport failure leaves dispatch uncertain, RPR keeps the pathway as write_status_unknown rather than silently retrying or reporting success.

Unreleased read-only server preview

The current source tree also contains a Phase 1 local stdio MCP server that inspects an existing RPR SQLite database through a read-only connection.

python -m pip install -e .
rpr-mcp --database ./rpr.sqlite3

It exposes only:

rpr.get_status
rpr.list_pathways
rpr.get_pathway
rpr.get_evidence
rpr.list_unresolved

It has no approval, execution, transition, reconciliation, repair, or resume tool. The database is opened with SQLite mode=ro, and status output does not disclose its filesystem path.

Release boundary: This read-only MCP server is an unreleased source preview. It is not included in the published PyPI 0.1.0a2 package. Read-only access can still reveal pathway definitions and retained evidence, so it is intended only for a trusted local MCP client with existing operating-system read permission.

See the MCP integration guide or the Japanese guide.

Verified in the public alpha

• pathway registration and authorized state transitions;
• persistent pathway and execution-attempt stores;
• Human Gate, repair, resume, and reconciliation boundaries;
• local-file, allow-listed HTTP, durable outbound-message, and real MCP subprocess paths;
• MCP server/tool admission binding, stdio execution, fault injection, and ambiguous-call handling;
• HTTP fault injection;
• crash/restart continuity and duplicate-dispatch prevention;
• backup, restore, diagnostics, uninstall, package/CLI residue checks, and customer-data retention;
• wheel and source-distribution build and installation checks;
• GitHub Actions OIDC Trusted Publishing to PyPI;
• English-primary and Japanese-parallel product documentation;
• Lean 4 verification of selected published state-machine invariants;
• Chromium and Pyodide execution of the CI-built RPR wheel in the public browser demo.

The read-only MCP server preview has additional source-tree tests for read-only database opening, MCP initialization and tools, malformed requests, missing pathways, stdout cleanliness, and rejection of missing or non-RPR databases. Those tests do not promote the preview into the published 0.1.0a2 release.

We need field-test reports for

RPR is public so real users can report reproducible environment and integration findings. Please open an Issue for:

• Windows, macOS, other Linux distributions, containers, and Python environments beyond the final Linux/Python 3.11 rehearsal;
• proxy, TLS, enterprise identity, credential handling, remote MCP, and service-specific connectivity;
• framework, agent, CI/CD, RPA, batch, and application integrations;
• installation, upgrade, backup/restore, removal, and operational usability;
• confusing states, missing examples, documentation gaps, and unsupported assumptions.

A user report is field evidence for that environment. It does not imply universal production readiness.

Quick Start

Install the Public Alpha from PyPI in an isolated, disposable environment:

python3.11 -m venv .venv
. .venv/bin/activate
python -m pip install --upgrade pip
python -m pip install responsibility-pathway-runtime==0.1.0a2
rpr --help

For development, source inspection, or the unreleased read-only MCP server preview, clone the public repository and use an editable install:

git clone https://github.com/YutoriKomeiji/responsibility-pathway-runtime.git
cd responsibility-pathway-runtime
python -m pip install -e .

To inspect the runtime without installing it locally, use the live browser demo. The demo runs the CI-built RPR wheel in Pyodide with SQLite; only the external payment provider is simulated.

The pre-release verification hashes remain recorded in release-evidence/replacement-freeze-2026-08-02.json. They are evidence for the frozen candidate that preceded the PyPI publication, not a substitute for reading the published package metadata and release state.

Integration boundary

The host application remains responsible for authentication, credential isolation, network controls, bypass prevention, domain-specific authorization, MCP peer selection, tool permissions, trusted-client access to stored pathway data, and the independent readback source. RPE integration is optional; RPE absence, malformed output, or unsupported results must not become implicit permission.

Documentation

• Product, scope, and architecture
• MCP integration
• Installation, operations, and recovery
• Security, limitations, integration, and API
• Verification, known issues, release notes, and UAT
• Support and field testing
• Security reporting
• Contributing

License

RPR is released under the MIT License. Copyright © 2026 Akihisa Ono.