Support matrix

This page describes the public Kit surface that Paybond supports today across direct SDK usage, agent runtime integrations, MCP hosts, and protocol/A2A clients. If a capability is not listed here, treat it as outside the standard SDK contract unless you have an explicit agreement with Paybond.

Language SDKs

Framework adapter parity

Each bilingual framework ships TypeScript and Python docs, exports, and smoke commands on the same page — complete sandbox smoke in either language without reading the other kit's docs. TypeScript-only frameworks link to @paybond/kit from Python with a clear redirect.

Smoke flags (all frameworks): add --operation <name>, --requested-spend-cents <n>, --evidence-preset <id>, and --format json. The same command works from the TypeScript CLI (npx -p @paybond/kit paybond …) or the Python CLI (paybond-kit …). Bilingual framework docs include TypeScript and Python wiring sections on one page.

Maturity notes: Claude Agents governs custom MCP tools only — built-in SDK tools (Read, Bash, …) stay unguarded unless you remove them from allowedTools. Vercel AI and Cloudflare Agents govern locally executed registry tools; provider-executed tools bypass unless adapter.deny_provider_executed_tools: true in paybond.policy.yaml or denyProviderExecutedTools: true on adapter helpers (see adapter docs).

Python optional extras for smoke: base pip install paybond-kit is enough for agent demo generic smoke. LangGraph, Claude Agents, OpenAI Agents, MCP, CrewAI, Pydantic AI, Google ADK, and Microsoft Agent Framework smoke commands require paybond-kit[langgraph], paybond-kit[claude-agents], paybond-kit[openai-agents], paybond-kit[mcp], paybond-kit[crewai], paybond-kit[pydantic-ai], paybond-kit[google-adk], or paybond-kit[microsoft-agent-framework] respectively. TypeScript Google ADK smoke requires optional peer @google/adk (npm install @google/adk). TypeScript Mastra smoke requires optional peer @mastra/core (npm install @mastra/core). TypeScript Cloudflare Agents smoke requires optional peers agents and ai (npm install agents ai). With pipx, quote extras on zsh, use pipx install 'paybond-kit[langgraph]' (or pipx inject paybond-kit langgraph langchain-core when base paybond-kit is already installed), and pass paybond explicitly on one-shot runs: pipx run --spec 'paybond-kit[langgraph]' paybond …. See Python quickstart — pipx and LangGraph adapter — Scaffold and smoke.

Planned framework adapters

These frameworks do not have native Paybond runner helpers yet. Paybond plans to add them in the order below. Use agent-agnostic or MCP today for spend controls on any framework. Request a native adapter if your stack needs one sooner.

Provider-agnostic agent runtime and host integrations

Paybond verifies tenant scope, intent capabilities, and tool operation names. The Kit does not depend on a specific model provider; callers can use the same spend-guard pattern with hosted models, local models, custom orchestrators, or MCP-compatible hosts.

Agent policy and middleware docs

Settlement rails

Rail availability does not imply universal variable-cost settlement. For managed completion_budget_v1, live positive partial settlement is supported on Stripe Connect, Stripe ACH, authorized Shopify orders, and Adyen; Stripe Connect and authorized Shopify orders also support zero by cancel/void. Stripe ACH and Adyen reject zero before provider effects. Stripe MPP charge, x402/Coinbase, Shopify Payments app, Flutterwave, and Paystack reject variable-cost terminal settlement before provider effects; Tempo sessions keep their existing cumulative voucher metering. See the exact public per-rail matrix.

Sandbox tenants can request stripe_ach_debit through the same SDK and admin routing surfaces, but Paybond routes those sandbox intents to simulator destinations. Tenant sandbox testing does not require STRIPE_SECRET_KEY or a real Stripe test-mode Connect account; those credentials are only needed for Paybond's optional Stripe ACH provider smoke tests.

Completion presets

Paybond ships a shared completion preset catalog (kit/completion-presets/catalog.json) consumed by Harbor, Gateway, CLI, and docs. Archetypes (api_response_ok, webhook_confirmed, …) and vendor packs (stripe_charge, ach_travel_booking, x402_saas_api_purchase, x402_travel_booking, invoice_payment_confirmed, …) define evidence schemas and Harbor template bindings.

Pick a preset aligned with your settlement rail — see Funding vs completion.

Gateway contracts (service accounts)

The Gateway deployment must accept service-account credentials on GET /v1/auth/principal and proxy recognition-gated intent mutations under /harbor/*.

Intent HTTP API (Kit-facing)

Signal HTTP API (Kit-facing)

Protocol and A2A Gateway API (Kit-facing)

CLI intent mutations (paybond intents create, fund, evidence, and settlement-confirm) delegate to paybond.harbor.* with replay-safe x-paybond-agent-recognition-proof headers rather than raw Gateway POSTs. Read-only operator commands (paybond intents list|get) stay on direct HTTP.

Compliance audit export API (Kit-facing)

CLI paybond audit exports list|get|delete|verify delegates to the SDK rather than duplicating Gateway HTTP. Export job creation is SDK-only (paybond.audit.exports.create); use the Operator Console or SDK for POST /v1/compliance/audit-exports. See Ledger and provenance for bundle structure and verification.

Boundaries

Local dev mocks (x402 fund parity)

Use paybond.intents.fundWithX402 / fund_with_x402 against these mocks to rehearse signing and polling without Coinbase or a remote sandbox API.

Compatibility expectations

Paybond validates the supported SDK and integration surfaces in automated testing before release. If you depend on a specific runtime or framework combination, validate it in your own CI against the public quickstarts and examples before rollout.

Sandbox access

To try Kit with a tenant-bound sandbox, create a self-serve Free Developer workspace, issue sandbox service-account keys from the console, and start with one-command guardrails.