Who contributed to Anthropic on May 19, 2026?

3 developers shipped this update, including rlancemartin, tobinsouth, and localden.

What were the notable Anthropic updates?

feat(managed_agents): Slack stateless webhook bridge template, Add SHA bump pipeline, policy scan, and MCP URL liveness check, and Fix dead MCP server URLs in bundled plugins (apollo, outreach, datadog; remove servicenow).

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The Wire · Showcase

CLAUDE MANAGED AGENTS NOW STATELESS ON SLACK

By RepoJournal · Filed 06:02 UTC on May 19, 2026 · About Anthropic

3 people shipped this

tobinsouth @tobinsouth 2 cited

rlancemartin @rlancemartin 1 cited

localden @localden 1 cited

A new webhook bridge template lets Slack @mentions trigger Claude agent runs without holding any session state, and the plugin ecosystem is tightening its MCP URL verification to catch dead endpoints before users do.

The Slack webhook bridge [1] ships a minimal TypeScript/Bun template that routes Slack Events API mentions directly to Claude Managed Agents using CMA outbound webhooks. No SSE streams held open. No session map database. Slack fires the event, Claude runs to idle on Anthropic infrastructure, then posts the result back via webhook. It's the stateless pattern the entire agent ecosystem has been moving toward, and it's now drop-in ready.

Meanwhile, the plugin marketplace is getting serious about URL validation. The knowledge-work-plugins repo added automated SHA bumping, policy scanning, and MCP URL liveness checks [2] to match claude-plugins-official's CI. That same sync caught four dead MCP server endpoints in the bundled job-function plugins [3]. Apollo, Outreach, and Datadog URLs have all been corrected and verified live; ServiceNow's entry was removed entirely because no shared hosted endpoint exists. Every Desktop user who launched an agent with those bundles hit connect failures on spawn. This fix rolls out silently on next app launch.

Over in claude-plugins-official, the nightly SHA bump pipeline scaled from 20 to 130 [4], so a single run can now clear any backlog without blocking on a single bad upstream. The verdict cache prevents re-burning Claude time on already-scanned SHAs. A new CI check [5] validates HTTP and SSE MCP server URLs on every bump PR, catching dead endpoints before they ship. A separate PR corrected source configs for plugins whose upstream layouts moved, unblocking RevenueCAT and others from the bump queue indefinitely.

Action items

→ Review the Slack managed agents template and consider migrating from session-holding SSE patterns anthropics/claude-cookbooks [plan]
→ Verify your bundled plugin MCP URLs if you ship job-function collections or knowledge-work plugins anthropics/knowledge-work-plugins [monitor]
→ Check if your external plugins are now picked up by the automated SHA bump (backlog should clear tonight) anthropics/claude-plugins-official [monitor]

References

[1] feat(managed_agents): Slack stateless webhook bridge template ↗ anthropics/claude-cookbooks
[2] Add SHA bump pipeline, policy scan, and MCP URL liveness check ↗ anthropics/knowledge-work-plugins
[3] Fix dead MCP server URLs in bundled plugins (apollo, outreach, datadog; remove servicenow) ↗ anthropics/knowledge-work-plugins
[4] Raise bump cap with verdict cache and skip-and-revert (#1913) anthropics/claude-plugins-official
[5] Add CI check for HTTP MCP server URL liveness ↗ anthropics/claude-plugins-official

Quick answers

What shipped in Anthropic on May 19, 2026?: A new webhook bridge template lets Slack @mentions trigger Claude agent runs without holding any session state, and the plugin ecosystem is tightening its MCP URL verification to catch dead endpoints before users do. In total, 12 commits and 13 pull requests landed.
Who contributed to Anthropic on May 19, 2026?: 3 developers shipped this update, including rlancemartin, tobinsouth, and localden.
What were the notable Anthropic updates?: feat(managed_agents): Slack stateless webhook bridge template, Add SHA bump pipeline, policy scan, and MCP URL liveness check, and Fix dead MCP server URLs in bundled plugins (apollo, outreach, datadog; remove servicenow).

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