Close Crm

REST API at api.close.com/api/v1/. Leads: standard CRUD at /lead/ with custom fields, status, and address data. Contacts: /contact/ linked to leads with name, email, phone, and title. Opportunities: /opportunity/ with value, confidence, date_won, and pipeline stages. Activities: separate endpoints for each type — /activity/email/, /activity/call/, /activity/meeting/, /activity/note/. Search: POST to /data/{object_type}/search/ with complex query objects supporting AND/OR/NOT conditions across fields. Custom fields are defined per object type. Bulk operations: /data/import/ for CSV-based bulk creation. Webhooks deliver events for lead, contact, opportunity, and activity changes. The API is well-designed with consistent patterns and strong search capabilities. Pagination uses _skip and _limit with has_more indicator.

Close CRM is built for inside sales teams with built-in calling, email, and SMS — no separate integrations needed for communication channels. For agents, the REST API is comprehensive: leads (companies), contacts (people), opportunities (deals), activities (calls, emails, meetings, notes), tasks, and custom objects. The lead-centric data model groups contacts and opportunities under leads. Activity logging captures all communication automatically when using Close's built-in channels. Smart Views provide saved searches with complex filter criteria. Sequences automate multi-step outreach. For agents building sales automation — lead enrichment, activity logging, opportunity tracking, outreach scheduling — Close's API covers the full sales workflow. The built-in communication channels mean agents don't need separate API integrations for sending emails or making calls.

API key authentication via HTTP Basic Auth (API key as username, empty password). Keys are generated per-user in Close settings. API key inherits the user's role permissions — admin keys have full access, member keys have member-level access. No fine-grained key scoping beyond the user role. OAuth 2.0 is available for third-party application integrations. API keys don't expire. For agents, creating a dedicated API user with appropriate role permissions provides clean access scoping. The role-based permission model means agents can be restricted to read-only or member-level operations. OAuth follows the standard authorization code flow with refresh tokens. The auth model is clean and well-aligned with CRM access patterns.

Developer documentation at developer.close.com is well-organized with API reference, authentication guide, and webhook documentation. The API reference covers every endpoint with parameters, response examples, and field descriptions. The search query syntax is well-documented with examples for common patterns. Custom field documentation explains type-specific behaviors (date, enum, text, number). Code examples use cURL throughout. Python client library is official and maintained. The documentation includes rate limiting guidance with best practices for high-volume operations. For agents, the lead search and activity creation docs are the most important starting points. Community resources are modest but the official documentation is comprehensive for the API's scope.

API errors return JSON with error and field-level error details. Standard HTTP status codes. Rate limits: per-organization with generous defaults — limits are dynamic and vary by endpoint. 429 responses include Retry-After header and rate limit headers (X-Rate-Limit-Limit, X-Rate-Limit-Remaining, X-Rate-Limit-Reset). Search endpoints have separate, tighter rate limits. Webhook delivery retries on failure. The search API can timeout on complex queries across large datasets — agents should paginate and use specific filters. Activity creation validates data shapes and returns field-specific errors. The API is generally reliable with predictable error behavior. For agents, monitoring rate limit headers proactively (before hitting 429) enables smooth operation.