Forward Deployed Engineer – Agent Runtimes & MCP (Python)

Recurring Decimal Inc.; Phoenix (AZ); On-site; USD 140,000 - 180,000; Full time

Job summary

Recurring Decimal Inc. seeks an experienced Python developer to build the Agent Trust integration for agentic commerce within Claude’s tooling. You will implement trust checks, identity binding at session start, and server-side enforcement for merchant integrations.

Expect work across storefronts, gateways, and companion tools with a focus on low latency and robust error handling. You will stand up runtimes, write an advisory MCP server, and author a merchant integration guide, measuring

Qualifications

• 5+ years of Python with asyncio, type hints and testing.
• Experience shipping LLM agents on Claude APIs or Agent SDK.
• Experience building MCP servers with authentication front and server-side enforcement.
• JWT/JWKS verification, OAuth client credentials, secrets handling.
• Ability to read unfamiliar open-source code quickly with citations.

Responsibilities

• Stand up blueprint verticals on all runtimes and run tests.
• Implement AgentTrustMixin for storefront and merchant backends.
• Build and test storefront MCP server path behind authenticating gateway.
• Write MCP server tools and a companion skill for Claude Code plugin.
• Author merchant integration guide and measure acceptance metrics.

Skills

Python

Asyncio

Typed code

pytest

ruff

Subclassing backends

Exception mapping

Claude API

Agent SDK

JWT/JWKS

OAuth

Latency budgeting

Open-source code reading

Tools

Claude Messages API

Agent SDK

MCP servers

HTTP authentication

real-time risk API

Job description

This role builds the Agent Trust integration for agentic commerce into Anthropic's Claude Commerce Agents blueprint and the surrounding Claude tooling, with the goal of making it adoptable by merchant engineers in a day.

First 90 days

• Stand up the blueprint's verticals on all three runtimes, run its test and verification suites, and pin and maintain fork compatibility.
• Implement the AgentTrustMixin for the blueprint's StorefrontBackend / MerchantBackend. This covers identity binding at session start, in-path trust checks on cart and checkout hooks, decision mapping to native tool-result semantics (Unavailable, domain errors), per-hook fail policy, PII-free decision logging, and outcome reporting.
• Build and test the storefront MCP server path for Managed Agents behind an authenticating gateway, with vault-credential and signed-claim identity options.
• Write the Agent Trust MCP server (advisory tools) and a companion skill for the blueprint's commerce-builder Claude Code plugin.
• Author the merchant integration guide and measure merchant effort (files, lines, prompt bytes, gates, time-to-first-verified-session) as an acceptance metric.

Must have

• 5+ years of Python with strong asyncio, typed code, pytest, and ruff, plus comfort subclassing abstract backends and mapping exceptions to structured results.
• Experience shipping tool-using LLM agents on the Claude Messages API or Agent SDK, and an understanding of prompt caching and why static-prefix bytes matter.
• Experience building or integrating MCP servers (streamable HTTP) with authentication in front, and an understanding that a model can skip a tool call, so enforcement must live server-side.
• JWT/JWKS verification, OAuth client credentials, and secrets handling, plus the ability to call a real-time risk API within a latency budget and reason about fail-open vs. fail-closed.
• Ability to read unfamiliar, unmaintained open-source code quickly, cite module and line for every claim, and work from written acceptance criteria without supervision.

Nice to have

• Claude Managed Agents beta (agents, environments, sessions, vaults, always_ask semantics)
• Claude Code plugin/skill authoring
• Bedrock/Vertex/Foundry routing
• E-commerce domain (cart, variants, checkout hand-off)
• Node 22 for example storefronts

• agent-trust-commerce Python package
• Managed Agents gateway variant
• Agent Trust MCP server
• commerce-builder companion skill
• Integration guide
• Retail vertical demo