Fonoster
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Comparison · Comms
Shortwave vs Slack
A side-by-side editorial comparison of Shortwave and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:mcp
Shortwave vs Slack: at a glance
What is Shortwave?
Shortwave keeps folding autonomy into the inbox, one AI action at a time.
Shortwave has moved decisively from an AI-assisted email client to an inbox that acts on the user's behalf. The assistant reads, drafts, organizes, and — via the Tasklet integration — triggers automated workflows across thousands of apps, with its work surfaced inside Shortwave rather than buried in Gmail. Every release since late 2024 has pushed more of the email workflow out of the user's hands and into the model's.
What is Slack?
Slack raises the Marketplace bar back to ten installs while the agent platform consolidates.
Slack's developer platform runs two tracks. The agent build-out has produced a spark roughly every two weeks since June — MCP client, a skills plugin targeting Claude Code and Cursor, and Slack Code — and now has a consolidation date attached: assistant_view is deprecated in February 2027, replaced by an Agent Sessions API. The second track is platform administration and tooling, and this window belongs to it: Marketplace submissions again require at least ten installed active workspaces, held throughout the review, after a period at a lower temporary threshold. The CLI has shipped three times since late July.
Shortwave vs Slack: editorial side-by-side
Shortwave
0.0COMMS
Shortwave keeps folding autonomy into the inbox, one AI action at a time.
◆ Current state
Shortwave has moved decisively from an AI-assisted email client to an inbox that acts on the user's behalf. The assistant reads, drafts, organizes, and — via the Tasklet integration — triggers automated workflows across thousands of apps, with its work surfaced inside Shortwave rather than buried in Gmail. Every release since late 2024 has pushed more of the email workflow out of the user's hands and into the model's.
◆ Where it's heading
The direction is a steadily widening action surface: MCP connectors to external tools, AI Memories, voice, and now trigger-based automation all frame email as an agent runtime rather than a reading pane. Model choices track the frontier closely — Claude 3.7 to Sonnet 4 to the 4.6 family — keeping capability tied to whatever the best available model can do. The team ships broadly across web, desktop, iOS, and Android each cycle.
◆ Prediction
The next moves most likely deepen autonomous execution — more trigger types and tighter loops where the assistant acts with less confirmation — rather than adding new surface features.
Slack
6.3COMMSCOLLAB
Slack raises the Marketplace bar back to ten installs while the agent platform consolidates.
◆ Current state
Slack's developer platform runs two tracks. The agent build-out has produced a spark roughly every two weeks since June — MCP client, a skills plugin targeting Claude Code and Cursor, and Slack Code — and now has a consolidation date attached: assistant_view is deprecated in February 2027, replaced by an Agent Sessions API. The second track is platform administration and tooling, and this window belongs to it: Marketplace submissions again require at least ten installed active workspaces, held throughout the review, after a period at a lower temporary threshold. The CLI has shipped three times since late July.
◆ Where it's heading
The install requirement moving back up is a distribution decision arriving in the middle of a platform push, and the two point the same way. Slack is making it easier to build agents and harder to list one, which favours developers who already have distribution — existing workspace tools and vendors — over a new app hoping the Marketplace supplies its first users. Combined with the assistant deprecation and the Agent Sessions API, the platform is narrowing on one agent surface and one class of builder rather than widening the funnel.
◆ Prediction
The threshold is described as a return from a temporary lower bar rather than a new policy, so the open question is what replaces the Marketplace as the discovery path for an app that cannot reach ten workspaces on its own. These entries do not answer it.
Alternatives to Shortwave and Slack
Other Comms products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Shortwave or Slack.
Element
Element 1.12.33 ships: simpler recovery keys, mandatory verification, no libolm migration.
Tawk.to
tawk.to's widget 4.4.0 turns to keyboard and screen-reader fixes after a run of form work.
Krisp
Krisp 2.83.4 brings Voice Translation into conference calls and lightens Accent Conversion.
Pixelfed
Pixelfed 0.15.2 ships the PHP RCE patches and turns cached timelines on for everyone.
Salesmsg
Salesmsg Reviews can now trigger follow-ups automatically based on a customer's latest rating.
See all Shortwave alternatives → · See all Slack alternatives →
Recent activity from Shortwave and Slack
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1mo agoSlackUpdated installation requirement for Slack Marketplace apps
- 1mo agoSlackCLI adds app-approval status checks and custom app icons
- 2mo agoSlackAnnouncing Slack Code ⚡
- 2mo agoSlackAgent Sessions API replaces assistant_view, deprecated Feb 2027
- 3mo agoSlackAnnouncing the Slack MCP and Skills Plugin ⚡
- 3mo agoSlackCLI adds manifest diff and a Block Kit preview command
- 8mo agoShortwaveUpgraded to Claude Sonnet & Opus 4.6
- 9mo agoShortwaveFully automate your email with Tasklet 🔗 ⚡
- 1y agoShortwaveEnhanced AI performance & collaboration
- 1y agoShortwaveIntegrate the AI with all your apps 🔌 ⚡
- 1y agoShortwaveTalk to your inbox 🎙️
- 1y agoShortwaveOrganize your inbox with AI ✨
Frequently asked questions
What is the difference between Shortwave and Slack?
Both compete on the same themes — mcp — within Comms. Slack is currently shipping more aggressively (velocity 6.3 vs 0.0), with 0 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Shortwave better than Slack?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Slack is currently shipping more aggressively (velocity 6.3 vs 0.0), with 0 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.
What are the best alternatives to Shortwave?
Top Shortwave alternatives in Comms are ranked by recent ship velocity. Browse the "Shortwave alternatives" section above for the current picks, or visit /alternatives/shortwave for the full list with editorial commentary on each.
What are the best alternatives to Slack?
Top Slack alternatives in Comms are ranked by recent ship velocity. Browse the "Slack alternatives" section above for the current picks, or visit /alternatives/slack for the full list with editorial commentary on each.