AddSign

AddSign is an electronic signature platform tailored for small businesses and freelancers. It offers a free forever plan with AI‑powered document analysis, unlimited signers, and legally binding e‑signatures. Users can upload, sign, and send documents in seconds, making it a cost‑effective DocuSign alternative. The service targets industries such as real estate, contracting, law firms, and creative professionals.

AddSign is listed with 1 API on the APIs.io network. Tagged areas include E-Signature, Small Business, AI Document Analysis, DocuSign Alternative, and Free Plan.

AddSign’s developer surface includes getting-started guide, engineering blog, pricing, and 11 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

15.1/100 emerging ▼ -5.2 Agent 4/100 human only Heartbeat 97/100 alive Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemium

1 API

E-Signature Small BusinessAI Document AnalysisDocuSign AlternativeFree Plan

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 15.1/100 · emerging

Contract Quality 0.0 / 21

Developer Ergonomics 2.4 / 17

Access Clarity 6.3 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 4.9 / 9

Regulatory Posture 1.5 / 15

Agent readiness — 4/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 5 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) 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.

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

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/.

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Agent readiness — checks not met, largest first (exact, from this profile):

Machine-Readable Contract +18 pts — api_specs includes an OpenAPI document
MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
Machine-Readable Auth +10 pts — a served openid-configuration/oauth-authorization-server carrying `issuer` (served), else the securitySchemes class in the provider OpenAPIs — bound (mutualTLS, DPoP, Signature) > negotiable (oauth2 authorizationCode/clientCredentials, openIdConnect) > bearer (http bearer, apiKey)
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes

12 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Quality scores 0.0 — up to +25.0 composite points
Developer Ergonomics scores 14.3 — up to +17.1 composite points
Operational Transparency scores 0.0 — up to +13.0 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/addsign-io/apis.yml: open an issue on github.com/api-evangelist/addsign-io to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Standards implemented 1

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

OAuth 2.0 Protected Resource Metadata

measured — observed by APIs.io (verified)

APIs 1

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

AddSign API

AddSign provides electronic signature capabilities via its web platform and MCP endpoint.

AddSign API pricing

Prices published by AddSign. A free plan or tier is listed.

Plan	Price
Free	Free plan: 8 documents/month, unlimited signers, up to 3 templates, AI overview (5/week)
Pro	Pro plan: $9.99/month — unlimited documents, unlimited templates, unlimited AI overview, c

Plan details, limits and sources →

Pricing Plans 1

Published pricing tiers and plan structures.

Addsign Io Plans Pricing

2 plans

PLANS

Security Posture 1

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

Addsign Io Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 1

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt

LLMsTxt

WellKnown

WellKnown

Build 2

SDKs, sample code, and the tooling you integrate with

SDKs

SDKs

Packages

Packages

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Commercial 4

Pricing, plans, and the legal terms of use

Plans

Pricing

TermsOfService

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

Hosts

Hosts

Vendors

Vendors

Source (apis.yml)

aid: addsign-io
name: AddSign
description: AddSign is an electronic signature platform tailored for small businesses and freelancers. It offers a free forever
  plan with AI‑powered document analysis, unlimited signers, and legally binding e‑signatures. Users can upload, sign, and
  send documents in seconds, making it a cost‑effective DocuSign alternative. The service targets industries such as real
  estate, contracting, law firms, and creative professionals.
url: https://artifacts.apis.io/addsign-io/apis.yml
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: low
  probe_state: gated
  source:
  - plans
  - security
  generated: '2026-11-06'
  method: derived
image: https://addsign.io/icons/icon-512x512.png
x-type: company
x-source: harvest:mcp-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-10-31 (modular-v1; was harvest)
specificationVersion: '0.20'
created: '2026-10-31'
modified: '2026-10-31'
tags:
- E-Signature
- Small Business
- AI Document Analysis
- DocuSign Alternative
- Free Plan
tags_raw:
- Electronic Signature
- Small Business
- AI Document Analysis
- DocuSign Alternative
- Free Plan
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Plans
  url: plans/addsign-io-plans-pricing.yml
- type: LLMsTxt
  url: llms/addsign-io-llms.txt
- type: WellKnown
  url: well-known/addsign-io-well-known.yml
- type: Hosts
  url: hosts/addsign-io-hosts.yml
- type: Vendors
  url: vendors/addsign-io-vendors.yml
- type: SDKs
  url: packages/addsign-io-packages.yml
- type: Packages
  url: packages/addsign-io-packages.yml
- type: GettingStarted
  url: https://addsign.io/blog/recruiters-onboarding-texas
- type: DomainSecurity
  url: security/addsign-io-domain-security.yml
- type: Website
  url: https://addsign.io/
- type: Blog
  url: https://addsign.io/blog
- type: Pricing
  url: https://addsign.io/pricing
- type: TermsOfService
  url: https://addsign.io/terms
- type: PrivacyPolicy
  url: https://addsign.io/privacy
apis:
- name: AddSign API
  description: AddSign provides electronic signature capabilities via its web platform and MCP endpoint.
  humanURL: https://addsign.io
  aid: addsign-io:addsign-api
x-coverage:
  state: gated
  reason: auth-required
  detail: MCP endpoint https://addsign.io/api/mcp returns 401 Unauthorized, blocking contract access.
  evidence:
  - url: https://addsign.io/api/mcp
    status: 401
  checked: '2026-10-31'
x-enrichment:
  date: '2026-10-31'
  status: enriched
  artifacts_added: 13
  pass: modular-v1
  engine: identity=oss,contract=oss,surfaces=oss,docs=oss,regulatory=oss

AddSign API — frequently asked questions

Does AddSign have an API?

Yes. APIs.io lists 1 API from AddSign, including AddSign API.

How much does the AddSign API cost?

AddSign publishes its prices; its Free plan is Free plan: 8 documents/month, unlimited signers, up to 3 templates, AI overview (5/week) as of 2026-10-31. APIs.io lists 2 pricing plans for AddSign, with each plan's price, limits and inclusions under Pricing on this page.

Is the AddSign API ready for AI agents?

AddSign has a Kin Score of 15.1 out of 100 (emerging) and an Agent Readiness score of 3.6 (human-only), scored by API Evangelist on 2026-11-06.

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get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
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apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
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