Affinity

Affinity is the CRM private capital firms run on — venture capital, private equity, private credit, investment banking, and family offices. It captures every email and calendar event across the firm automatically, turns that history into scored relationships, and organizes deals as rows on Lists whose columns each firm defines for itself.

Why Affinity?

Relationship intelligence, not just records: Every pair of people carries an interaction score derived from real communication, so "who here can introduce me" is a query rather than a Slack thread.
No manual entry: Emails, meetings, calls, and chat messages are captured and attributed on their own. The API reads that history as first-class objects.
Lists are the data model: A deal lives as a row on a List, and the List's columns are the fields the firm actually tracks. Field IDs are discoverable at runtime, so a workflow adapts to a firm's schema instead of hardcoding it.
A change feed built for sync: Field value changes are exposed as an ordered, cursor-paged stream, which is what makes an incremental mirror possible without re-reading the whole workspace.

Using Affinity in Sim

Sim's Affinity integration covers the v2 API end to end with an API key — 70 operations across companies, people, opportunities, lists, list entries, saved views, fields, notes, reminders, merges, interactions, transcripts, and users. Field values are readable and writable one at a time or a hundred per request, and the discovery operations (List Field Metadata, List List Fields, and the dropdown-option operations) exist so an agent can learn a workspace's schema before it writes to it.

Key benefits of using Affinity in Sim:

Pipeline reporting: Page a List or a Saved View with exactly the columns a report needs, then summarize what moved, what stalled, and what is closing.
Writing back: Move a deal's stage, fill an enriched field, or update a hundred columns on one row in a single call — with the dropdown option resolved by name first, so nothing is written blind.
Warm introductions: Combine relationship scores with the inferred-connection operations, which surface paths through shared employment history and through investors who backed a company a target once led.
Meeting capture: Read a transcript fragment by fragment and write the summary back as a note anchored to that meeting, attached to the companies and people it concerns.
Natural-language sourcing: Semantic Search takes an investment thesis in plain language and returns scored companies; Search Notes and Search Files answer diligence questions from what the firm already wrote down.
Incremental sync: Follow the field-value change feed from a stored cursor to keep a table or warehouse in step without a full reload.

Before you start

Generate an API key from the Manage Apps page in your Affinity settings; it authenticates as a bearer token. Two things gate what you will actually see:

License. The Affinity APIs are only available on select license types. Monthly call limits follow the plan tier — 100k on Scale and Advanced, unlimited on Enterprise — alongside a per-user limit of 900 calls per minute shared with the v1 API. Exceeding either returns a 429.
Permissions. The API respects in-product sharing, so it never returns a list, note, or interaction the key's user cannot already see. Several operations additionally require a role-based permission an Affinity admin grants: Export All Organizations directory for listing and searching companies, Export All People directory for listing and searching people, Export data from Lists for opportunities and for reading or writing list entries, Manage duplicates plus an admin role for merges, and Manage Users for user email addresses and roles.

Some Affinity endpoints are still marked BETA — company, person, and list-entry search, the per-entity field-value reads, the inferred-connection operations, and the user operations. Affinity may change those without notice or versioning.

Usage Instructions

Integrates the Affinity v2 API into the workflow. Read and search companies, people, and opportunities, page the rows of any list or saved view, read and write field values one at a time or a hundred at once, write and reply to notes, create reminders, follow logged calls, emails, meetings, and transcripts, find warm introductions through shared work and investment history, search notes and files by keyword, find companies from a description in plain language, and follow the field-value change feed for delta sync. What each operation can reach depends on the permissions granted to the API key.

Actions

Affinity Batch Update Entity Fields

Write up to 100 non-list field values on one company or person in a single request.

Parameter	Type	Required	Description
`apiKey`	string	Yes	Affinity API key, sent as a bearer token
`entityType`	string	Yes	Which entity to write the fields on: companies or persons
`entityId`	string	Yes	ID of that company or person
`updates`	json	Yes	Up to 100 field updates as [{"id":"<fieldId>","value":{"type":"…","data":…}}], using the same value shapes as a single field update

Parameter	Type	Required	Description
`apiKey`	string	Yes	Affinity API key, sent as a bearer token
`listId`	string	Yes	The list ID
`listEntryId`	string	Yes	The list entry ID
`updates`	json	Yes	Up to 100 field updates as [{"id":"<fieldId>","value":{"type":"…","data":…}}], using the same value shapes as a single field update

Parameter	Type	Required	Description
`apiKey`	string	Yes	Affinity API key, sent as a bearer token
`name`	string	Yes	Name of the new list
`type`	string	Yes	Entity kind the list holds: company, opportunity, or person
`isPublic`	boolean	No	Whether everyone in the organization can see the list

Parameter	Type	Description
`id`	number	The list's unique identifier
`name`	string	The list name
`creatorId`	number	User who created the list
`ownerId`	number	User who owns the list
`isPublic`	boolean	Whether the list is visible to the organization
`createdAt`	string	When the list was created
`type`	string	company, opportunity, or person — the entity kind the list holds