https://seamless.engineering/api-changelog/slack/ Every Slack API change our daily monitoring detects: breaking changes, deprecations and additions. en Sat, 10 Oct 2026 00:10:15 GMT 720 https://seamless.engineering/api-changelog/slack/#dec81bbd6556 slack-dec81bbd6556 Thu, 17 Sep 2026 12:00:00 GMT New feature New feature (2026-08-28). Slack CLI v4.7.0: Added app request status command, custom app icons support, and improved help template for Slack CLI. https://seamless.engineering/api-changelog/slack/#cf9d84d4487f slack-cf9d84d4487f Wed, 16 Sep 2026 12:00:00 GMT New feature New feature (2026-09-15). Slack CLI v4.8.0: New CLI features including manifest sync command, --manifest-source flag, code_channels support, and bug fixes for interactive prompts. https://seamless.engineering/api-changelog/slack/#2dff8856366d slack-2dff8856366d Thu, 03 Sep 2026 12:00:00 GMT New feature New feature (2026-08-31). Slack CLI v4.7.0: New Slack CLI version adds app request status checking command, custom app icon support, and fixes help template display of hidden subcommands. https://seamless.engineering/api-changelog/slack/#42eba0578a83 slack-42eba0578a83 Tue, 01 Sep 2026 12:00:00 GMT Other Other (2026-09-01). Slack Marketplace app submissions now require minimum 10 active workspace installations, increased from temporary lower threshold. https://seamless.engineering/api-changelog/slack/#421ce7e02b8b slack-421ce7e02b8b Mon, 31 Aug 2026 12:00:00 GMT New feature New feature (2026-07-30). Slack CLI v4.6.0: Added manifest diff command and Block Kit Builder preview command to Slack CLI. https://seamless.engineering/api-changelog/slack/#7f1e932de86e slack-7f1e932de86e Mon, 31 Aug 2026 12:00:00 GMT Breaking Breaking (2026-07-15). Bolt for JS v5 - Node.js 20+ requirement: Bolt for JS v5 requires Node.js 20+, removes Workflow Steps from Apps, removes proxy/TLS configuration options, and updates respond() to return native Response objects. https://seamless.engineering/api-changelog/slack/#4df88dd38842 slack-4df88dd38842 Mon, 31 Aug 2026 12:00:00 GMT Breaking Breaking (2026-07-14). Multiple Node Slack SDK package updates: Major version updates across Node SDK packages requiring Node.js 20+, with significant breaking changes in socket-mode, web-api, and webhook packages related to HTTP transport. https://seamless.engineering/api-changelog/slack/#8765089b1011 slack-8765089b1011 Sat, 22 Aug 2026 12:00:00 GMT New feature New feature (2025-02-03). New markdown-specific block added to Block Kit for better markdown content rendering. https://seamless.engineering/api-changelog/slack/#ea9cd49267cc slack-ea9cd49267cc Sat, 22 Aug 2026 12:00:00 GMT New feature New feature (2026-08-20). Apps now receive agent_session_stopped event when users stop an agent stream, enabling proper handling of agent termination. https://seamless.engineering/api-changelog/slack/#113178b31a61 slack-113178b31a61 Sat, 22 Aug 2026 12:00:00 GMT Deprecation Deprecation (2026-08-20). Assistant messaging experience (assistant_view) will be deprecated in February 2027, replaced by new Agent Sessions API with agents.sessions.setStatus and agents.sessions.rename methods. https://seamless.engineering/api-changelog/slack/#d7a9afdaf168 slack-d7a9afdaf168 Thu, 20 Aug 2026 12:00:00 GMT New feature New feature (2026-08-20). New feature allowing agents and people to collaborate in dedicated channels with code diffs, Block Kit views, HTML previews, and Canvases for shared artifact work. https://seamless.engineering/api-changelog/slack/#93b0bdca5da0 slack-93b0bdca5da0 Thu, 20 Aug 2026 12:00:00 GMT Deprecation Deprecation (2026-08-20). The assistant_view messaging experience will be deprecated in February 2027 and replaced by the new Agent Sessions API with agents.sessions.setStatus and agents.sessions.rename methods. https://seamless.engineering/api-changelog/slack/#a57dbb7d2ac8 slack-a57dbb7d2ac8 Wed, 19 Aug 2026 12:00:00 GMT New feature New feature (2026-07-02). New app_context_changed event and app_context field in message.im and app_home_opened events to provide context about user's active view. https://seamless.engineering/api-changelog/slack/#c29a1949b1e2 slack-c29a1949b1e2 Wed, 19 Aug 2026 12:00:00 GMT Other Other (2026-07-13). Desktop notifications changed to prioritize text from blocks over top-level text field, mobile notifications continue using message.text only. https://seamless.engineering/api-changelog/slack/#d09026e710c5 slack-d09026e710c5 Wed, 19 Aug 2026 12:00:00 GMT Breaking Breaking (2026-06-17). Breaking change: system notifications now sent from USLACK instead of Slackbot, requires apps to update logic filtering by Slackbot user ID or username. https://seamless.engineering/api-changelog/slack/#0cc45c1815bb slack-0cc45c1815bb Mon, 17 Aug 2026 12:00:00 GMT Other Other (2025-04-11). Classic apps deprecation timeline has been adjusted multiple times; currently paused as of December 2025. https://seamless.engineering/api-changelog/slack/#67946deefc29 slack-67946deefc29 Sun, 16 Aug 2026 12:00:00 GMT New feature New feature (2026-04-10). Slack CLI v4.0.0 and v4.0.1: Slack CLI v4.0.0 includes new AI Agent templates with IT support agent, improved environment variable management with .env file loading before hooks, and better template categorization for slack create command. https://seamless.engineering/api-changelog/slack/#0160c5c70306 slack-0160c5c70306 Thu, 13 Aug 2026 12:00:00 GMT New feature New feature (2026-07-21). Slack CLI v4.5.0: Added Claude Code plugin recommendation, reduced verbose output, new --category flag for docs search, and improved error messages. https://seamless.engineering/api-changelog/slack/#050beb8161eb slack-050beb8161eb Wed, 05 Aug 2026 12:00:00 GMT New feature New feature (2026-05-19). Slack CLI v4.1.0: Added slack api method command, screen reader accessibility support, env init command, mcp_server and optional OAuth scopes manifest support. https://seamless.engineering/api-changelog/slack/#a3f838c91a9d slack-a3f838c91a9d Fri, 31 Jul 2026 12:00:00 GMT New feature New feature (2026-07-31). New Slack MCP and Skills Plugin for Claude Code and Cursor with AI-focused skills and direct Slack workspace interaction capabilities. https://seamless.engineering/api-changelog/slack/#421ce7e02b8b slack-421ce7e02b8b Fri, 31 Jul 2026 12:00:00 GMT New feature New feature (2026-07-30). Slack CLI v4.6.0: Added slack manifest diff command to show differences between project manifest and app settings, and slack blocks preview command for Block Kit Builder. https://seamless.engineering/api-changelog/slack/#74b4524a785e slack-74b4524a785e Fri, 24 Jul 2026 12:00:00 GMT New feature New feature (2026-06-30). New agent_view messaging experience replacing assistant_view, with changes to app_home_opened events, suggested prompts location, and conversation continuation logic. https://seamless.engineering/api-changelog/slack/#0160c5c70306 slack-0160c5c70306 Tue, 21 Jul 2026 12:00:00 GMT New feature New feature (2026-07-21). Slack CLI v4.5.0: Added category flag to docs search, improved non-TTY error messages for prompts, fixed JSON parsing errors from empty files, and reduced verbose output. https://seamless.engineering/api-changelog/slack/#3ee48723de28 slack-3ee48723de28 Fri, 17 Jul 2026 12:00:00 GMT New feature New feature (2026-04-16). Added alert, card, and carousel blocks to Block Kit with streaming API support for blocks in chat methods. https://seamless.engineering/api-changelog/slack/#7f1e932de86e slack-7f1e932de86e Thu, 16 Jul 2026 12:00:00 GMT Breaking Breaking (2026-07-15). Bolt for JS v5: Major version bump requiring Node.js 20+, removes Workflow Steps from Apps, migrates from axios to Fetch API, removes deprecated proxy/TLS configuration options. https://seamless.engineering/api-changelog/slack/#c29a1949b1e2 slack-c29a1949b1e2 Tue, 14 Jul 2026 12:00:00 GMT Other Other (2026-07-13). Slack desktop client notifications now extract text from blocks first before falling back to top-level text field; mobile notifications unchanged. https://seamless.engineering/api-changelog/slack/#4df88dd38842 slack-4df88dd38842 Tue, 14 Jul 2026 12:00:00 GMT Breaking Breaking (2026-07-14). Multiple Node Slack SDK package updates: All Node Slack SDK packages now require Node.js 20+; web-api updated to v8, webhook updated to v8, socket-mode updated to v3, all migrating from axios to Fetch API. https://seamless.engineering/api-changelog/slack/#576b5d412b88 slack-576b5d412b88 Tue, 14 Jul 2026 12:00:00 GMT New feature New feature (2026-06-03). Slack CLI v4.2.0: Added unauthenticated request support to slack api command, improved Y/N prompts, disabled upgrade notifications for manifest commands. https://seamless.engineering/api-changelog/slack/#89f53adcb7ac slack-89f53adcb7ac Sat, 11 Jul 2026 12:00:00 GMT New feature New feature (2026-02-11). New plan and task card blocks allow apps to display agent thinking steps and task progress to users. https://seamless.engineering/api-changelog/slack/#e225e7b52c4f slack-e225e7b52c4f Wed, 08 Jul 2026 12:00:00 GMT New feature New feature (2026-06-30). Python Slack SDK v3.43.0: Added public ts property to ChatStream, made thread_ts optional for setSuggestedPrompts method. https://seamless.engineering/api-changelog/slack/#2891fd90c16c slack-2891fd90c16c Wed, 08 Jul 2026 12:00:00 GMT New feature New feature (2026-05-18). Python Slack SDK v3.42.0: Added authorship arguments to assistant and chat methods, highlight_type support for file uploads, new Block Kit blocks support. https://seamless.engineering/api-changelog/slack/#a57dbb7d2ac8 slack-a57dbb7d2ac8 Thu, 02 Jul 2026 12:00:00 GMT New feature New feature (2026-07-02). New app_context_changed event and app_context field in message.im and app_home_opened events allow agent apps to receive context about user's current viewing location (channel, DM, thread, canvas, list). https://seamless.engineering/api-changelog/slack/#971d9b8dc15e slack-971d9b8dc15e Thu, 02 Jul 2026 12:00:00 GMT Deprecation Deprecation (2025-06-05). Timeline for retiring api.slack.com has been adjusted. https://seamless.engineering/api-changelog/slack/#06764179f7e0 slack-06764179f7e0 Thu, 02 Jul 2026 12:00:00 GMT Other Other (2024-12-10). Slack App Developer Policy has been updated. https://seamless.engineering/api-changelog/slack/#ecddc6f2a2b8 slack-ecddc6f2a2b8 Thu, 02 Jul 2026 12:00:00 GMT Other Other (2024-12-05). API documentation is migrating from api.slack.com to docs.slack.dev. https://seamless.engineering/api-changelog/slack/#74b4524a785e slack-74b4524a785e Tue, 30 Jun 2026 12:00:00 GMT New feature New feature (2026-06-30). New agent_view feature deprecates assistant_view for agent conversations, changing DM detection to use app_home_opened event instead of assistant_thread_started and making thread_ts optional for suggested prompts. https://seamless.engineering/api-changelog/slack/#e225e7b52c4f slack-e225e7b52c4f Tue, 30 Jun 2026 12:00:00 GMT New feature New feature (2026-06-30). Slack CLI v4.4.0: Slack CLI v4.4.0 adds support for features.agent_view app manifest property to enable the new Agent messaging experience. https://seamless.engineering/api-changelog/slack/#7f1a87e6e3ba slack-7f1a87e6e3ba Mon, 29 Jun 2026 12:00:00 GMT New feature New feature (2026-06-29). Container block is now available for Block Kit use. https://seamless.engineering/api-changelog/slack/#0d5d69cf697e slack-0d5d69cf697e Mon, 29 Jun 2026 12:00:00 GMT New feature New feature (2026-06-18). Slack CLI v4.3.0: Added --app flag to create command, external-auth add-secret for all apps, and mcp_server manifest field support. https://seamless.engineering/api-changelog/slack/#67946deefc29 slack-67946deefc29 Mon, 29 Jun 2026 12:00:00 GMT New feature New feature (2026-04-10). Slack CLI v4.0.0 and v4.0.1: Major CLI version with agent development templates, environment variable management, file watching with live reload, and improved Python project handling. https://seamless.engineering/api-changelog/slack/#efdca3169999 slack-efdca3169999 Fri, 26 Jun 2026 12:00:00 GMT New feature New feature (2026-02-19). Updates and improvements to Slack CLI. https://seamless.engineering/api-changelog/slack/#c9494ae75fc7 slack-c9494ae75fc7 Fri, 26 Jun 2026 12:00:00 GMT New feature New feature (2026-06-03). Added unauthenticated request support to slack api command, improved UI formatting, disabled upgrade notifications for manifest commands. https://seamless.engineering/api-changelog/slack/#f15b699297be slack-f15b699297be Fri, 19 Jun 2026 12:00:00 GMT New feature New feature (2026-06-18). New version adds --app flag for scaffolding, external-auth command availability, and MCP server manifest field support. https://seamless.engineering/api-changelog/slack/#6238f5e1ca9d slack-6238f5e1ca9d Thu, 18 Jun 2026 12:00:00 GMT New feature New feature (2026-06-18). New Slackbot MCP Client allowing developers to connect MCP servers with multiple authentication methods for tool discovery and invocation. https://seamless.engineering/api-changelog/slack/#67946deefc29 slack-67946deefc29 Thu, 18 Jun 2026 12:00:00 GMT New feature New feature (2026-04-10). Slack CLI v4.0.0 and v4.0.1: Major release with agent development focus: new AI agent templates (Starter and IT Support agents), environment variable management (.env files loaded before hooks), file watch with live reload, improved Python project setup with virtual environments, and refreshed prompt UI. https://seamless.engineering/api-changelog/slack/#6343daf526c3 slack-6343daf526c3 Thu, 18 Jun 2026 12:00:00 GMT New feature New feature (2026-03-19). Slack CLI v3.15.0: Normalized project directory names to kebab-case, improved app name prompt with placeholder text, switched to local manifest.json by default, and updated slack app link command. https://seamless.engineering/api-changelog/slack/#ab6341db5c61 slack-ab6341db5c61 Thu, 18 Jun 2026 12:00:00 GMT New feature New feature (2026-03-05). Bug fixes and improvements to Slack CLI tooling. https://seamless.engineering/api-changelog/slack/#06b8414c1b77 slack-06b8414c1b77 Thu, 18 Jun 2026 12:00:00 GMT New feature New feature (2026-05-19). CLI adds slack api command for direct API method calls, screen reader support, env init command, MCP server manifest support, and optional OAuth scopes. https://seamless.engineering/api-changelog/slack/#050beb8161eb slack-050beb8161eb Wed, 17 Jun 2026 12:00:00 GMT New feature New feature (2026-05-19). Slack CLI v4.1.0: Added slack api command to call any API method directly, improved accessibility support, added env init command, added MCP server manifest field support, added optional OAuth scopes support, improved icon handling and auto-detection. https://seamless.engineering/api-changelog/slack/#ac096405d86f slack-ac096405d86f Wed, 17 Jun 2026 12:00:00 GMT Breaking Breaking (2026-06-17). Breaking change: System notifications migrated from Slackbot (U025AQVCU) to new Slack system user (USLACK); apps filtering by Slackbot user ID or username must update integration logic. https://seamless.engineering/api-changelog/slack/#6c315d16d7dd slack-6c315d16d7dd Tue, 16 Jun 2026 12:00:00 GMT New feature New feature (2026-06-16). Data visualization block is now available for Block Kit use. https://seamless.engineering/api-changelog/slack/#53c95ce5ac56 slack-53c95ce5ac56 Mon, 08 Jun 2026 12:00:00 GMT New feature New feature (2026-05-19). Slack CLI v4.1.0 adds slack api command to call any API method directly, improved environment variable management, and support for optional OAuth scopes. https://seamless.engineering/api-changelog/slack/#c5fa945f4f36 slack-c5fa945f4f36 Fri, 05 Jun 2026 12:00:00 GMT Breaking Breaking (2025-02-27). Major Slack CLI version 3.0.0 released with significant features and improvements. https://seamless.engineering/api-changelog/slack/#576b5d412b88 slack-576b5d412b88 Thu, 04 Jun 2026 12:00:00 GMT New feature New feature (2026-06-03). Java Slack SDK v1.49.0: Added authorship arguments to assistant.threads.setStatus and chat.startStream methods; added highlight_type support to file upload methods. https://seamless.engineering/api-changelog/slack/#576b5d412b88 slack-576b5d412b88 Thu, 04 Jun 2026 12:00:00 GMT New feature New feature (2026-06-03). Slack CLI v4.2.0: Added unauthenticated request support to slack api command, disabled upgrade notifications for manifest commands, and improved Y/N prompt displays. https://seamless.engineering/api-changelog/slack/#43a45b87da5b slack-43a45b87da5b Wed, 03 Jun 2026 12:00:00 GMT New feature New feature (2025-10-22). New Work Objects feature enabling structured data management and collaboration within Slack. https://seamless.engineering/api-changelog/slack/#3768663e5343 slack-3768663e5343 Thu, 21 May 2026 12:00:00 GMT New feature New feature (2025-09-11). New features and improvements to developer tools. https://seamless.engineering/api-changelog/slack/#bac995f55361 slack-bac995f55361 Thu, 21 May 2026 12:00:00 GMT New feature New feature (2025-09-25). New features and improvements to developer tools. https://seamless.engineering/api-changelog/slack/#43a26e6e0f4a slack-43a26e6e0f4a Thu, 21 May 2026 12:00:00 GMT New feature New feature (2025-10-21). New features and improvements to CLI tooling. https://seamless.engineering/api-changelog/slack/#434e048b9df0 slack-434e048b9df0 Thu, 21 May 2026 12:00:00 GMT New feature New feature (2025-01-30). New Data Access API released for accessing Slack workspace data. https://seamless.engineering/api-changelog/slack/#233e89dce074 slack-233e89dce074 Wed, 20 May 2026 12:00:00 GMT New feature New feature (2026-05-20). Data table block is now available for Block Kit use. https://seamless.engineering/api-changelog/slack/#06b8414c1b77 slack-06b8414c1b77 Tue, 19 May 2026 12:00:00 GMT New feature New feature (2026-05-19). New CLI features including slack api command, screen reader support, env management improvements, and MCP Server configuration support. https://seamless.engineering/api-changelog/slack/#24596fb52d74 slack-24596fb52d74 Fri, 15 May 2026 12:00:00 GMT New feature New feature (2026-04-10). Major update focused on AI agent development with scaffold templates, file watching with live reload, environment variable management, and agent framework support including Claude, OpenAI, and Pydantic AI. https://seamless.engineering/api-changelog/slack/#341503081977 slack-341503081977 Thu, 14 May 2026 12:00:00 GMT New feature New feature (2026-05-13). Five new tools added to Slack MCP server: add reactions, create conversations, list channel members, list emoji, and read files. https://seamless.engineering/api-changelog/slack/#8bd72554869c slack-8bd72554869c Thu, 14 May 2026 12:00:00 GMT New feature New feature (2023-09-29). Rich text formatting capabilities added to Block Kit surfaces for more expressive messaging. https://seamless.engineering/api-changelog/slack/#d368e7ac5e37 slack-d368e7ac5e37 Tue, 12 May 2026 12:00:00 GMT New feature New feature (2026-02-19). Slack CLI v3.13.0: Highlighted agentic apps in slack create agent command, added --list flag to show templates without immediate selection, and improved login prompts. https://seamless.engineering/api-changelog/slack/#70ba6ced8091 slack-70ba6ced8091 Thu, 07 May 2026 12:00:00 GMT Other Other (2025-06-03). Clarification provided on rate limit changes for non-Marketplace apps. https://seamless.engineering/api-changelog/slack/#08ef0e91d43b slack-08ef0e91d43b Thu, 07 May 2026 12:00:00 GMT Breaking Breaking (2024-04-11). New creation of classic apps and legacy custom integration bots has been discontinued. https://seamless.engineering/api-changelog/slack/#dc30b1764686 slack-dc30b1764686 Thu, 07 May 2026 12:00:00 GMT New feature New feature (2024-01-17). New file upload functionality added to Block Kit enabling file uploads in messages and modals. https://seamless.engineering/api-changelog/slack/#cab8bdcb827b slack-cab8bdcb827b Thu, 07 May 2026 12:00:00 GMT Breaking Breaking (2025-02-27). The Slack CLI deno command is being removed from the platform. https://seamless.engineering/api-changelog/slack/#76d5d83279d9 slack-76d5d83279d9 Thu, 07 May 2026 12:00:00 GMT New feature New feature (2024-01-16). New capability to securely render internal images in modals and messages with proper authorization. https://seamless.engineering/api-changelog/slack/#47a77e6fa7df slack-47a77e6fa7df Tue, 21 Apr 2026 12:00:00 GMT New feature New feature (2024-09-16). New Agents & AI Apps feature released enabling development of AI-powered agent applications. https://seamless.engineering/api-changelog/slack/#a6a0be48e1ce slack-a6a0be48e1ce Tue, 21 Apr 2026 12:00:00 GMT Other Other (2025-05-29). Slack API Terms of Service have been updated; developers should review changes to ensure compliance. https://seamless.engineering/api-changelog/slack/#70c1d57850cc slack-70c1d57850cc Tue, 21 Apr 2026 12:00:00 GMT New feature New feature (2024-08-14). Custom workflow steps feature now available to all Slack apps providing workflow extensibility. https://seamless.engineering/api-changelog/slack/#45d05fb8b4dc slack-45d05fb8b4dc Tue, 21 Apr 2026 12:00:00 GMT Deprecation Deprecation (2024-09-01). Breaking change: Legacy custom bots and classic apps support is being discontinued affecting older app implementations. https://seamless.engineering/api-changelog/slack/#ade68ba13a0a slack-ade68ba13a0a Tue, 21 Apr 2026 12:00:00 GMT Deprecation Deprecation (2025-03-17). Timeline for files.upload method deprecation has been extended; developers should migrate to new file upload methods. https://seamless.engineering/api-changelog/slack/#d0105afc6c30 slack-d0105afc6c30 Tue, 21 Apr 2026 12:00:00 GMT Other Other (2025-05-29). Rate limits for non-Marketplace apps have been updated, requiring apps to adjust their API call patterns accordingly. https://seamless.engineering/api-changelog/slack/#0c6fb2dfa781 slack-0c6fb2dfa781 Tue, 21 Apr 2026 12:00:00 GMT Breaking Breaking (2025-03-27). api.slack.com is being retired; developers must migrate to docs.slack.dev for API documentation and references. https://seamless.engineering/api-changelog/slack/#73d4ab618b73 slack-73d4ab618b73 Tue, 21 Apr 2026 12:00:00 GMT Other Other (2025-03-10). Slack platform API and tools documentation is now available in beta on docs.slack.dev, providing early access to updated content. https://seamless.engineering/api-changelog/slack/#77c362e61dcd slack-77c362e61dcd Tue, 21 Apr 2026 12:00:00 GMT Deprecation Deprecation (2024-05-16). Breaking deprecation: files.upload method is deprecated and will be replaced by sequenced Web API methods. https://seamless.engineering/api-changelog/slack/#29fca440dd21 slack-29fca440dd21 Tue, 21 Apr 2026 12:00:00 GMT Other Other (2025-04-10). Slack CLI released as open source software. https://seamless.engineering/api-changelog/slack/#3ee48723de28 slack-3ee48723de28 Thu, 16 Apr 2026 12:00:00 GMT New feature New feature (2026-04-16). Three new Block Kit blocks (alert, card, carousel) added and streaming API methods updated to support streaming blocks. https://seamless.engineering/api-changelog/slack/#641ef113ecad slack-641ef113ecad Mon, 13 Apr 2026 12:00:00 GMT New feature New feature (2026-03-19). Updates include kebab-case project directory normalization, local manifest.json default for Bolt projects, manifest source detection, and app manifest overwrite warnings. https://seamless.engineering/api-changelog/slack/#1645da87d159 slack-1645da87d159 Sun, 12 Apr 2026 12:00:00 GMT New feature New feature (2025-07-21). New API for creating and managing featured workflow templates in Slack. https://seamless.engineering/api-changelog/slack/#707a1fb71bb6 slack-707a1fb71bb6 Fri, 10 Apr 2026 12:00:00 GMT New feature New feature (2025-02-03). New markdown block added to Block Kit. https://seamless.engineering/api-changelog/slack/#abe1158d186d slack-abe1158d186d Fri, 10 Apr 2026 12:00:00 GMT New feature New feature (2025-09-02). New Lists API for creating and managing list data structures in Slack. https://seamless.engineering/api-changelog/slack/#67946deefc29 slack-67946deefc29 Fri, 10 Apr 2026 12:00:00 GMT New feature New feature (2026-04-10). Slack CLI v4.0.0 and v4.0.1: Major CLI update with agent development focus including new AI Agent templates, environment variable management from .env files, file watching with live reloading, local manifest management, and improved Python project support. https://seamless.engineering/api-changelog/slack/#434e048b9df0 slack-434e048b9df0 Fri, 10 Apr 2026 12:00:00 GMT New feature New feature (2025-01-30). New Data Access API released for secure access to Slack data through search interface. https://seamless.engineering/api-changelog/slack/#48e5e94d4e54 slack-48e5e94d4e54 Tue, 31 Mar 2026 12:00:00 GMT New feature New feature (2025-10-07). New features released specifically designed for Slack apps that send AI responses, including streaming text and other AI-related capabilities. https://seamless.engineering/api-changelog/slack/#2da0e0b6f759 slack-2da0e0b6f759 Mon, 30 Mar 2026 12:00:00 GMT New feature New feature (2026-03-30). PKCE (Proof Key for Code Exchange) authentication flow is now generally available for enhanced security. https://seamless.engineering/api-changelog/slack/#c05578dcf13e slack-c05578dcf13e Thu, 26 Mar 2026 12:00:00 GMT Other Other (2025-10-28). OAuth page redesigned with improved user experience. https://seamless.engineering/api-changelog/slack/#a4f609fdd9e3 slack-a4f609fdd9e3 Thu, 26 Mar 2026 12:00:00 GMT New feature New feature (2026-02-17). New Slack MCP server and Real-time Search API released, enabling AI-powered search and tool integration capabilities. https://seamless.engineering/api-changelog/slack/#89f53adcb7ac slack-89f53adcb7ac Thu, 26 Mar 2026 12:00:00 GMT New feature New feature (2026-02-11). New Block Kit components (task_card, url source, plan blocks) and task_display_mode parameter for text-streaming API methods enable display of app actions. https://seamless.engineering/api-changelog/slack/#4692bcbb3f07 slack-4692bcbb3f07 Thu, 26 Mar 2026 12:00:00 GMT Deprecation Deprecation (2025-12-08). Classic apps deprecation timeline has been paused. https://seamless.engineering/api-changelog/slack/#efefee1451ac slack-efefee1451ac Thu, 26 Mar 2026 12:00:00 GMT Deprecation Deprecation (2025-07-29). Classic apps deprecation timeline has been extended. https://seamless.engineering/api-changelog/slack/#2682927a0d75 slack-2682927a0d75 Thu, 26 Mar 2026 12:00:00 GMT Deprecation Deprecation (2025-08-26). The allow_message_deletion field is being deprecated. https://seamless.engineering/api-changelog/slack/#8403727029cc slack-8403727029cc Thu, 26 Mar 2026 12:00:00 GMT Other Other (2025-07-08). Slack Marketplace apps now required to have minimum installations on active workspaces to be eligible for Marketplace submission. https://seamless.engineering/api-changelog/slack/#4a27f0ce0fdd slack-4a27f0ce0fdd Thu, 26 Mar 2026 12:00:00 GMT New feature New feature (2025-07-21). New featured workflows API available for discovering and managing featured workflows in the Slack platform. https://seamless.engineering/api-changelog/slack/#fe4698d5dc2b slack-fe4698d5dc2b Thu, 26 Mar 2026 12:00:00 GMT New feature New feature (2025-08-14). New table block available for Block Kit use. https://seamless.engineering/api-changelog/slack/#f01da4f689a9 slack-f01da4f689a9 Thu, 26 Mar 2026 12:00:00 GMT New feature New feature (2025-09-02). New Lists API released for managing lists in Slack workspaces.