Rspamd
Rspamd 4.3 fixes SPF evaluation order and rejects weak DKIM keys, with results that change.
Comparison · Comms
Slack vs Superhuman
A side-by-side editorial comparison of Slack and Superhuman — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:mcp
Slack vs Superhuman: at a glance
| Feature | Slack | Superhuman |
|---|---|---|
| Sector | Comms, Collab | Comms |
| Velocity score | 6.3 | 5.0 |
| Sparks · 30d | 1 | 0 |
| Top themes | agents, a2a, mcp, slackbot-skills | email, mcp, ai assistant, team admin |
| Last editorial update | 3d ago | 2d ago |
| Website | Visit → | — |
What is Slack?
Slack now hosts any A2A agent without Slack-specific code.
Slack's developer channel is almost all agent plumbing. On 10 November Slack became an A2A (Agent2Agent) client: a team hosts its own agent, publishes an Agent Card, and Slack calls it when people talk to it, with no request URL, event handling or Slack-specific logic. This follows Slackbot skills managed through Web API methods, a Slack CLI that points coding agents to the Slack MCP server, and a new requirement that Work Objects embeds allow the slack-mcps.com frame ancestor.
What is Superhuman?
Superhuman's MCP now lets Claude and ChatGPT attach files, set reminders and share threads.
Superhuman is a premium email client building a calendar, team comments and AI around its mail core. On 11 November its Mail MCP gained four abilities in Claude, ChatGPT and other AI tools: setting follow-up reminders, sending attachments, using private and team snippets, and sharing threads for team comments. The MCP stays on Business and Enterprise plans, a week after a team admin console reached every plan.
Slack vs Superhuman: editorial side-by-side
Slack
6.3COMMSCOLLAB
Slack now hosts any A2A agent without Slack-specific code.
◆ Current state
Slack's developer channel is almost all agent plumbing. On 10 November Slack became an A2A (Agent2Agent) client: a team hosts its own agent, publishes an Agent Card, and Slack calls it when people talk to it, with no request URL, event handling or Slack-specific logic. This follows Slackbot skills managed through Web API methods, a Slack CLI that points coding agents to the Slack MCP server, and a new requirement that Work Objects embeds allow the slack-mcps.com frame ancestor.
◆ Where it's heading
Slack is lowering the cost of putting outside agents in front of its users: first skills as code, then MCP pointers for coding agents, now a standard protocol in place of the Slack app model for agents. The platform is positioning itself as the place where agents built anywhere meet the people who use them.
◆ Prediction
Expect more A2A follow-ups, such as agents appearing in Slackbot or skills surfaces and richer Agent Card features, given how fast the agent releases have stacked up since October.
Superhuman
5.0COMMS
Superhuman's MCP now lets Claude and ChatGPT attach files, set reminders and share threads.
◆ Current state
Superhuman is a premium email client building a calendar, team comments and AI around its mail core. On 11 November its Mail MCP gained four abilities in Claude, ChatGPT and other AI tools: setting follow-up reminders, sending attachments, using private and team snippets, and sharing threads for team comments. The MCP stays on Business and Enterprise plans, a week after a team admin console reached every plan.
◆ Where it's heading
Superhuman is making its mail features callable from outside AI assistants rather than only from its own app. Each MCP addition maps an existing Superhuman feature, such as reminders, snippets or shared comments, onto a tool an assistant can use, with sharing gated on the user's confirmation. Keeping the MCP on paid team plans ties it to the admin and usage reporting shipped the week before.
◆ Prediction
More Superhuman features exposed through the MCP is the likely next step, with calendar and Auto Labels the obvious gaps; the entries do not show whether the MCP will reach lower plans.
Alternatives to Slack and Superhuman
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 Slack or Superhuman.
Twilio
Twilio's voice AI stops cutting callers off mid-sentence, using its own turn-taking model.
Salesmsg
Salesmsg adds call-back requests and a one-click Emergency Stop for all outbound texts.
Element
Element 1.12.35 follows the call picture-in-picture release with one desktop storage fix.
Krisp
Krisp moves call transcripts and live captions to cloud transcription in KrispCX 2.84.4.
Misskey
Misskey 2026.11 ships: a leaner start script, and Node.js 22 no longer boots.
See all Slack alternatives → · See all Superhuman alternatives →
Recent activity from Slack and Superhuman
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 2d agoSuperhumanSnippets in Claude, ChatGPT, and MCP ✂️
- 2d agoSuperhumanSharing & Commenting in Claude, ChatGPT, and MCP 🗯️
- 2d agoSuperhumanReminders in Claude, ChatGPT, and MCP ⏰
- 2d agoSuperhumanAttachments in Claude, ChatGPT, and MCP 📎
- 4d agoSlackBring your A2A agents to Slack ⚡
- 8d agoSlackWork Objects embeds require the slack-mcps.com frame ancestor
- 9d agoSuperhumanAdmin Tools 🛠️
- 10d agoSlackSlack CLI 4.13 tells coding agents about Slack MCP and Skills
- 10d agoSlackSlack Skills Plugin installs in Claude Code from its own marketplace
- 12d agoSlackUpdated low-usage submission criteria for Slack Marketplace apps
- 15d agoSlackSlack CLI 4.12.0, the fourth CLI release in October
- 21d agoSuperhumanSuperhuman Mail for iPhone Duo
Frequently asked questions
What is the difference between Slack and Superhuman?
Both compete on the same themes — mcp — within Comms. Slack is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 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 Slack better than Superhuman?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Slack is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 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 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.
What are the best alternatives to Superhuman?
Top Superhuman alternatives in Comms are ranked by recent ship velocity. Browse the "Superhuman alternatives" section above for the current picks, or visit /alternatives/superhuman for the full list with editorial commentary on each.