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ResiliReplay

ResiliReplay

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aliengineering-byte.github.ioDeveloper Tools2Updated 8w ago
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About ResiliReplay

ResiliReplay is a CLI for testing MCP server reliability through deterministic failures, bounded recovery, and executable regression tests. It is aimed at developers validating server behavior, with safety controls for reviewed and remote targets.

Key features

  1. 01Inject deterministic failures
  2. 02Test bounded recovery and retries
  3. 03Check duplicate side effects
  4. 04Generate and run regression tests
  5. 05Store evidence as metadata and hashes

Use cases

  1. 01Verify recovery after a predictable tool failure
  2. 02Check retries do not repeat side effects
  3. 03Create executable tests from causal failures

MCP support

ResiliReplay tests MCP servers and can run bounded failure-and-recovery checks against reviewed servers. It also supports an existing MCP audit workflow.

Configuration

Local server config is the same for every client. Copy it into your client’s MCP config file.

mcp.json · Universal config
{
  "mcpServers": {
    "aliengineering-byte-resilireplay": {
      "command": "npx",
      "args": [
        "-y",
        "resilireplay"
      ]
    }
  }
}
Run commandnpx -y resilireplay

Local servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.

Packages
npmresilireplay0.7.1

Tools

10

Saved tool list · updated 3w ago

This tool takes no parameters.

Details

From the project README

ResiliReplay

Inject deterministic MCP failures, verify bounded recovery and duplicate-effect behavior, and turn causal failures into executable regression tests.

npx --yes resilireplay@latest mcp demo

The demo is a bundled local fixture: no config, account, credential, paid model, telemetry, or remote target. It runs a clean call, reproduces one deterministic failure, retries once, records zero duplicate effects, generates and executes a regression, prints an evidence digest, and cleans up.

Test a reviewed server without starting it:

npx --yes resilireplay@latest mcp test --config ./mcp.json --server my-server --tool echo --safety inert --dry-run

Repeat the displayed plan with --approve <plan-sha256> to execute it. --json, --output, --no-regression, --timeout, and --retries map to the same bounded engine. The existing mcp audit workflow remains supported.

npx --yes resilireplay@latest mcp serve --help

Node.js 22 and 24 are supported. Evidence persists metadata and hashes instead of unrestricted tool bodies or credentials. Remote targets retain explicit ownership controls.

Agent-runtime capture, campaigns, replay, Studio, adapters, MCP-RES v0.1/v0.2, security guidance, and the real packed-package MCP Everything example are documented in the repository README.

Apache-2.0.

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