USPS
The United States Postal Service (USPS) provides a modern suite of RESTful APIs for address validation, domestic and international pricing, shipping label creation and cancellation, tracking, and service standards through its developer portal. The APIs replace the legacy Web Tools platform and use OAuth 2.0 Client Credentials for authentication. The platform supports both production and TEM (Testing Environment for Mailers) endpoints for developing and validating shipping integrations.
More than an index entry, but the surface is still mostly links rather than artifacts — the cohort most likely to move a full band from modest, well-targeted work.
API Evangelist profiles USPS the way a machine reads it — 7 machine-readable artifacts across 5 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — USPS scores 15.0/100 (emerging), with a separate agent-readiness read of 0/100 (human only). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile USPS
Each block below is one kind of artifact we hold for USPS. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 5
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
USPS OAuth 2.0
Token endpoint for OAuth 2.0 Client Credentials authentication used to authorize requests to all USPS API products.
USPS Addresses API
Verify and standardize US addresses to USPS specifications, reducing shipping delays and errors.
USPS Tracking API
Retrieve tracking status and delivery events for shipped packages across USPS services.
USPS Labels API
Create and cancel domestic shipping labels with integrated address standardization, pricing, and manifesting.
USPS Domestic Prices API
Retrieve current pricing information for USPS domestic shipping products and services.
GraphQL 1
Where a provider ships GraphQL, the schema is the contract. We profile it alongside the REST surface so the whole interface is legible in one place.
GraphQL schemas published by this provider.
USPS GraphQL Schema
Conceptual GraphQL schema for the United States Postal Service (USPS) APIs. This schema models the capabilities exposed by the USPS REST API developer portal at [https://develop...
GRAPHQLSecurity Posture 1
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Resources
Every other property we hold for USPS — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Get Started 2
Portal, sign-up, and the first successful call
Documentation 1
Reference material describing how the API behaves
Build 1
SDKs, sample code, and the tooling you integrate with
Access & Security 1
Authentication, authorization, and security posture
Company 3
The organization behind the API
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