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Head to head · Crm records · October 2026 research run

Affinity vs Capsule CRM

Affinity scores 63.4 (B) on agent readiness against Capsule CRM's 55.7 (C), and leads in 4 of 7 scored categories. Capsule CRM leads on reliability, payments & pricing and transparency & trust. Both do crm records.

AffinityProject Affinity, Inc. · HTTP API B63.4/100#311 of 722 Capsule CRMZestia Limited · HTTP API C55.7/100#504 of 722

Which one, for what

Affinity B

Good for Venture capital, private equity and other private capital firms that already run Affinity and want an agent to read relationship strength, pipeline lists, notes and meetings, then update fields and log notes.

Ahead on

  • Schema & documentation, 91 against 48
  • Agent ergonomics, 66 against 59
  • Security & auth, 66 against 46
  • Maintenance & community, 70 against 38

Also in its favour

  • Runs on your own machine

Watch for

No self-serve access. Every plan button reads Contact sales, the Essential plan has no API, and trial accounts can't call the API

Capsule CRM C

Good for Small teams already on Capsule who want an agent to read and write contacts, opportunities, projects and tasks over REST with a read-only scope available.

Ahead on

  • Reliability, 83 against 64
  • Payments & pricing, 30 against 10
  • Transparency & trust, 75 against 70

Also in its favour

  • Free to start without a card

Watch for

No OpenAPI file, llms.txt or official SDK was found

Score by category

CategoryWeight this runAffinityCapsule CRMEdge
Reliability16%206483Capsule CRM +19
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.29148Affinity +43
Agent ergonomics13%16.26659Affinity +7
Security & auth14%17.56646Affinity +20
Payments & pricing10%12.51030Capsule CRM +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87038Affinity +32
Transparency & trust7%8.87075Capsule CRM +5
Negative events≤1500
Total63.4 · B55.7 · C

Facts side by side

FactAffinityCapsule CRM
KindHTTP APIHTTP API
VendorProject Affinity, Inc.Zestia Limited
Hosted endpointhttps://api.affinity.co/v2https://api.capsulecrm.com/api/v2
TransportsHTTP, Streamable HTTP, stdioHTTP
AuthOAuth or keyOAuth or key
PricingPaidFreemium
x402nono
LicenceProprietary service under Affinity's master subscription agreement. The affinity-mcp package on PyPI is MITProprietary service under Capsule's Customer Terms
Tools exposed75none
Read-only variant documentedyesyes
llms.txtyesno
Last release2026-10-022026-09-25
Terms last updatedno date given
Privacy policy last updated2026-07-012025-08-21
Customer content may train modelsnot found in the text
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticeyes
Arbitration or class-action waivernot found in the text
Popularity268 PyPI/wknone

Verdicts

Affinity

A public OpenAPI 3.1 file, dated API versions with migration notes and a hosted MCP server with a read-only OAuth scope give an agent a well-documented way in. Access needs a Scale plan at $2,300 a user a year, sold through sales, with no trial that includes the API, and 36 of the 112 v2 operations are marked beta.

Capsule CRM

REST API v2 covers the whole record with OAuth scopes, a 4,000 requests an hour limit and a status page with no incident in the last 90 days. There is no OpenAPI file, llms.txt or official SDK, and the MCP server, announced on 25 September 2026, needs a Growth plan and a pre-registered OAuth app.

Before you call either

Affinity

  1. Send X-Affinity-Api-Version: 2026-09-17 on every request, or the key's default version applies. Unauthenticated calls answered as 2024-01-01 when we checked
  2. Read x-ratelimit-limit-user-remaining and x-ratelimit-limit-org-remaining on each response. The limits are 900 calls a minute per user and, below Enterprise, 100,000 a month per account, shared by v1, v2 and MCP
  3. Follow pagination.nextUrl for the next page, and pass fieldIds or fieldTypes so list calls return only the fields needed
  4. Check for duplicates before a create. There are no idempotency keys, so a retried POST can make a second record
  5. For MCP, untick the write scope at OAuth consent when the task only reads. Treat note, transcript and file text as untrusted input

Capsule CRM

  1. Send Authorization: Bearer <token> to https://api.capsulecrm.com/api/v2. Projects use the old name in paths, /kases
  2. Follow the Link header for the next page. perPage goes up to 100 and the default is 50
  3. On 429, wait until the epoch time in X-RateLimit-Reset. The docs suggest one second between calls
  4. Ask for the read scope when the task only reads. A write with a read-only token answers 403 with insufficient_scope
  5. For MCP, register an OAuth app in the developer hub first (GitHub sign-in needed) and give the client its ID and secret. Personal API tokens are refused

Questions

Which is better for AI agents, Affinity or Capsule CRM?

Affinity scores 63.4 (B) on agent readiness against Capsule CRM's 55.7 (C), and leads in 4 of 7 scored categories. Capsule CRM leads on reliability, payments & pricing and transparency & trust.

Do Affinity and Capsule CRM need an API key?

Both take an API key or an OAuth sign-in.

Can an agent call Affinity and Capsule CRM without installing anything?

Yes. Affinity has a hosted endpoint at https://api.affinity.co/v2 and Capsule CRM at https://api.capsulecrm.com/api/v2.

Other comparisons with Affinity or Capsule CRM

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