Abound

Abound was a US tax-compliance API company for platforms, marketplaces and fintechs serving the 1099 economy. Its v4 REST API covered the full information-return lifecycle: collecting Form W-9, W-8BEN and W-8BEN-E from payees, running real-time TIN verification against the IRS, then generating, filing, correcting, voiding and physically mailing Form 1099-NEC, 1099-MISC, 1099-K and 1099-INT to federal and state tax authorities. It also shipped drop-in UI components for payee onboarding, a 44-event webhook surface, and an official TypeScript SDK. Abound was acquired (announced November 2024) and the service has since been retired: the withabound.com DNS zone is fully de-delegated, the API and docs hosts no longer resolve, and the GitHub organization has been removed. This profile preserves the API surface, recovered from the first-party Fern API Definition shipped inside the official npm package.

Abound publishes 13 APIs on the APIs.io network, including 1099-INT API, 1099-K API, 1099-MISC API, and 10 more. Tagged areas include Company, Taxes, Tax Compliance, Regulatory Compliance, and Financial-Services.

The Abound catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Abound’s developer surface includes authentication, sandbox, and 20 more developer resources.

🌐 Visit website 📡 Source on GitHub
35.6/100 thin ▬ flat Agent 55/100 agent native Full breakdown ↓
scored 2026-08-20 · rubric v0.12.0
AccessSelf serve
13 APIs 1 MCP Servers
CompanyTaxesTax ComplianceRegulatory ComplianceFinancial-ServicesIdentity VerificationGovernmentDocumentsWebhookRetired

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-20 · rubric v0.12.0
Composite quality — 35.6/100 · thin
Contract Quality 14.7 / 21
Developer Ergonomics 4.8 / 17
Access Clarity 0.0 / 17
Operational Transparency 0.9 / 11
Contract Governance 1.7 / 10
Discoverability 6.9 / 9
Regulatory Posture 4.7 / 15
Agent readiness — 55/100 · agent native
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
Documented Reversibility 6 / 6
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 9 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 7 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 5 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Regulatory Posture applies to this provider. Its tags matched the Government & Public Sector regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.
The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/abound: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 13

Individual APIs this provider publishes, each with its own machine-readable definition.

Abound 1099-INT API

The 1099-INT API from Abound — 6 operation(s) for 1099-int.

Abound 1099-K API

The 1099-K API from Abound — 6 operation(s) for 1099-k.

Abound 1099-MISC API

The 1099-MISC API from Abound — 6 operation(s) for 1099-misc.

Abound 1099-NEC API

The 1099-NEC API from Abound — 6 operation(s) for 1099-nec.

Abound Access Tokens API

The Access Tokens API from Abound — 1 operation(s) for access tokens.

Abound Electronic Delivery Consents API

The Electronic Delivery Consents API from Abound — 1 operation(s) for electronic delivery consents.

Abound Mailings API

The Mailings API from Abound — 2 operation(s) for mailings.

Abound Tax Treaties API

The Tax Treaties API from Abound — 1 operation(s) for tax treaties.

Abound TIN Verifications API

The TIN Verifications API from Abound — 2 operation(s) for tin verifications.

Abound Users API

The Users API from Abound — 2 operation(s) for users.

Abound W-8BEN API

The W-8BEN API from Abound — 2 operation(s) for w-8ben.

Abound W-8BEN-E API

The W-8BEN-E API from Abound — 2 operation(s) for w-8ben-e.

Abound W-9 API

The W-9 API from Abound — 2 operation(s) for w-9.

Scroll for all 13

Open Collections 14

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

Abound API - v4 1099-INT API

OPEN COLLECTION

Abound API - v4 1099-INT 1099-K API

OPEN COLLECTION

Abound API - v4 1099-INT 1099-MISC API

OPEN COLLECTION

Abound API - v4 1099-INT 1099-NEC API

OPEN COLLECTION

Abound API - v4 1099-INT Access Tokens API

OPEN COLLECTION

Abound API - v4 1099-INT Electronic Delivery Consents API

OPEN COLLECTION

Abound API - v4 1099-INT Mailings API

OPEN COLLECTION

Abound API - v4 1099-INT Tax Treaties API

OPEN COLLECTION

Abound API - v4 1099-INT TIN Verifications API

OPEN COLLECTION

Abound API - v4 1099-INT Users API

OPEN COLLECTION

Abound API - v4 1099-INT W-8BEN API

OPEN COLLECTION

Abound API - v4 1099-INT W-8BEN-E API

OPEN COLLECTION

Abound API - v4 1099-INT W-9 API

OPEN COLLECTION

Scroll for all 14

Arazzo Workflows 3

Multi-step API workflows described with the Arazzo specification.

Collect a W-9 and verify the payee TIN

Create a user, collect their Form W-9, then run and read back a real-time TIN verification against the IRS.

ARAZZO

Correct or void a filed 1099-NEC

Fix a filed return - either file a correction or void it entirely. Both only work after the document is FILED.

ARAZZO

Create, file and mail a Form 1099-NEC

Run the full 1099-NEC lifecycle - create the document, file it with federal and state authorities, then mail the payee copy.

ARAZZO

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

Abound MCP Server

MCP SERVER

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Abound API v4 - Webhooks

The Abound webhook event surface: 44 HMAC-signed events covering Users, TIN Verifications, Mailings, Form 1099-INT/K/MISC/NEC and Forms W-9, W-8BEN and W-8BEN-E. Derived from th...

ASYNCAPI

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Abound Authentication

http · 1 scheme

SECURITY

Abound Domain Security

TLSv1.3 · DNSSEC · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Abound Agentic Access

55 operations · 33 acting

55 operations · 33 acting

AGENTIC

Resources

Get Started 1

Portal, sign-up, and the first successful call

Sandbox
Sandbox

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

AgentSkill
AgentSkill
 MCPServer
MCPServer
 LLMsTxt
LLMsTxt
 AgenticAccess
AgenticAccess

Design & Contract 11

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 Idempotency
Idempotency
 ErrorCatalog
ErrorCatalog
 Lifecycle
Lifecycle
 Conformance
Conformance
 DataModel
DataModel
 Components
Components
 Webhooks
Webhooks
 Arazzo
Arazzo
 Arazzo
Arazzo
 Arazzo
Arazzo

Scroll for all 11

Build 2

SDKs, sample code, and the tooling you integrate with

Packages
Packages
 SDKs
SDKs

Access & Security 2

Authentication, authorization, and security posture

Authentication
Authentication
 DomainSecurity
DomainSecurity

Company 1

The organization behind the API

Website
Website

Other 1

Properties that don't map to a standard resource type

Overlay
Overlay

Source (apis.yml)

apis.yml Raw ↑ 
aid: abound
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/abound.png
name: Abound
description: 'Abound was a US tax-compliance API company for platforms, marketplaces and fintechs serving the 1099 economy.
  Its v4 REST API covered the full information-return lifecycle: collecting Form W-9, W-8BEN and W-8BEN-E from payees, running
  real-time TIN verification against the IRS, then generating, filing, correcting, voiding and physically mailing Form 1099-NEC,
  1099-MISC, 1099-K and 1099-INT to federal and state tax authorities. It also shipped drop-in UI components for payee onboarding,
  a 44-event webhook surface, and an official TypeScript SDK. Abound was acquired (announced November 2024) and the service
  has since been retired: the withabound.com DNS zone is fully de-delegated, the API and docs hosts no longer resolve, and
  the GitHub organization has been removed. This profile preserves the API surface, recovered from the first-party Fern API
  Definition shipped inside the official npm package.'
url: https://raw.githubusercontent.com/api-evangelist/abound/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-tier: stub
x-tier-reason: portfolio-lead
x-status: retired
x-status-evidence: withabound.com has no delegated nameservers (NXDOMAIN on apex, www, docs, status, production-api and sandbox-api);
  github.com/withabound returns 404. Probed 2026-07-19.
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Taxes
- Tax Compliance
- Regulatory Compliance
- Financial-Services
- Identity Verification
- Government
- Documents
- Webhook
- Retired
tags_raw:
- Company
- Taxes
- Tax Compliance
- Regulatory Compliance
- Financial Services
- Identity Verification
- Government
- Documents
- Webhooks
- Retired
apis:
- aid: abound:abound-1099-int-api
  name: Abound 1099-INT API
  description: The 1099-INT API from Abound — 6 operation(s) for 1099-int.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - 1099-INT
  properties:
  - type: OpenAPI
    url: openapi/abound-1099-int-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-1099-k-api
  name: Abound 1099-K API
  description: The 1099-K API from Abound — 6 operation(s) for 1099-k.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - 1099-K
  properties:
  - type: OpenAPI
    url: openapi/abound-1099-k-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-1099-misc-api
  name: Abound 1099-MISC API
  description: The 1099-MISC API from Abound — 6 operation(s) for 1099-misc.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - 1099-MISC
  properties:
  - type: OpenAPI
    url: openapi/abound-1099-misc-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-1099-nec-api
  name: Abound 1099-NEC API
  description: The 1099-NEC API from Abound — 6 operation(s) for 1099-nec.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - 1099-NEC
  properties:
  - type: OpenAPI
    url: openapi/abound-1099-nec-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-access-tokens-api
  name: Abound Access Tokens API
  description: The Access Tokens API from Abound — 1 operation(s) for access tokens.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - Access Tokens
  properties:
  - type: OpenAPI
    url: openapi/abound-access-tokens-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-electronic-delivery-consents-api
  name: Abound Electronic Delivery Consents API
  description: The Electronic Delivery Consents API from Abound — 1 operation(s) for electronic delivery consents.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - Electronic Delivery Consents
  properties:
  - type: OpenAPI
    url: openapi/abound-electronic-delivery-consents-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-mailings-api
  name: Abound Mailings API
  description: The Mailings API from Abound — 2 operation(s) for mailings.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - Mailings
  properties:
  - type: OpenAPI
    url: openapi/abound-mailings-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-tax-treaties-api
  name: Abound Tax Treaties API
  description: The Tax Treaties API from Abound — 1 operation(s) for tax treaties.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - Tax Treaties
  properties:
  - type: OpenAPI
    url: openapi/abound-tax-treaties-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-tin-verifications-api
  name: Abound TIN Verifications API
  description: The TIN Verifications API from Abound — 2 operation(s) for tin verifications.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - TIN Verifications
  properties:
  - type: OpenAPI
    url: openapi/abound-tin-verifications-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-users-api
  name: Abound Users API
  description: The Users API from Abound — 2 operation(s) for users.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - User
  tags_raw:
  - Users
  properties:
  - type: OpenAPI
    url: openapi/abound-users-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-w-8ben-api
  name: Abound W-8BEN API
  description: The W-8BEN API from Abound — 2 operation(s) for w-8ben.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - W-8BEN
  properties:
  - type: OpenAPI
    url: openapi/abound-w-8ben-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-w-8ben-e-api
  name: Abound W-8BEN-E API
  description: The W-8BEN-E API from Abound — 2 operation(s) for w-8ben-e.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - W-8BEN-E
  properties:
  - type: OpenAPI
    url: openapi/abound-w-8ben-e-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
- aid: abound:abound-w-9-api
  name: Abound W-9 API
  description: The W-9 API from Abound — 2 operation(s) for w-9.
  humanURL: https://www.npmjs.com/package/@withabound/node-sdk
  baseURL: https://production-api.withabound.com
  tags:
  - W-9
  properties:
  - type: OpenAPI
    url: openapi/abound-w-9-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/abound-webhooks-asyncapi.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Overlay
  url: overlays/abound-v4-overlay.yaml
- type: Website
  url: https://withabound.com
- type: Packages
  url: packages/abound-packages.yml
- type: SDKs
  url: packages/abound-packages.yml
- type: Authentication
  url: authentication/abound-authentication.yml
- type: Conventions
  url: conventions/abound-conventions.yml
- type: Idempotency
  url: conventions/abound-conventions.yml
- type: ErrorCatalog
  url: errors/abound-problem-types.yml
- type: Lifecycle
  url: lifecycle/abound-lifecycle.yml
- type: Conformance
  url: conformance/abound-conformance.yml
- type: DataModel
  url: data-model/abound-data-model.yml
- type: Components
  url: components/abound-components.yml
- type: Sandbox
  url: sandbox/abound-sandbox.yml
- type: Webhooks
  url: asyncapi/abound-webhooks-asyncapi.yml
- type: AgentSkill
  url: skills/_index.yml
- type: MCPServer
  url: mcp/abound-mcp.yml
- type: LLMsTxt
  url: llms/abound-llms.txt
- type: DomainSecurity
  url: security/abound-domain-security.yml
- type: AgenticAccess
  url: agentic-access/abound-agentic-access.yml
- type: Arazzo
  name: Collect a W-9 and verify the payee TIN
  url: arazzo/abound-collect-w9-and-verify-tin.arazzo.yml
- type: Arazzo
  name: Create, file and mail a Form 1099-NEC
  url: arazzo/abound-file-1099-nec.arazzo.yml
- type: Arazzo
  name: Correct or void a filed 1099-NEC
  url: arazzo/abound-correct-or-void-1099.arazzo.yml
x-enrichment:
  date: '2026-07-20'
  status: minimal
  artifacts_added: 4
  pass: local-v1