🧭 Claude Code 2.1.265 Ships Plugin Directories, Session Resume Overhaul, and a 1 GB Tool-Result Cap — Followed by Same-Day 2.1.266 Patch

Two Claude Code releases landed on September 9 in quick succession. Version 2.1.265 is a broad quality-and-platform update — the most substantial single-version release in weeks. Version 2.1.266 shipped the same day as a surgical regression fix after a gateway-configuration bug was discovered in 2.1.265.

What 2.1.265 adds

• Plugin directory support: You can now point the plugin loader at a folder containing multiple manifests. Claude Code automatically detects added or removed children within that directory without requiring a restart or manual reload. This makes managing large plugin inventories — or plugins that ship as sibling files — dramatically simpler.
• Improved session resume with prompt caching: Subagent and teammate sessions now restore their tool lists and system prompts correctly on resume, and resume operations are wired into the prompt-cache path, meaning the re-attachment turn is cheaper than before.
• 1 GB cap on tool results saved to disk: Long-running agents that accumulate large tool outputs no longer risk unbounded disk writes. Results exceeding 1 GB are truncated with a visible indicator in the session context, preventing silent failures in overnight or multi-hour runs.
• VS Code: 14-day auto-archiving: Inactive VS Code sessions are now automatically archived after 14 days (configurable), keeping the sessions panel uncluttered for teams that open many exploratory Claude Code sessions.
• Windows AppContainer/sandboxed environment fix: File permission issues that blocked Claude Code from reading or writing inside Windows sandboxed environments are resolved.
• Slash-command list matching: The command picker now uses list-based matching rather than a single suggestion, so partial command names surface all matching options rather than committing to the first alphabetical hit.
• Additional fixes: Remote Control end-of-turn message sequencing, MCP server fallback handling for legacy HTTP+SSE transport, model-switch commands (/model opusplan now accepted), code syntax highlighting in permission prompts showing complete characters, and background session retirement prevented mid-turn.

The 2.1.266 regression fix

Within hours of 2.1.265 going out, Anthropic identified a regression in gateway and proxy handling. The undocumented CLAUDE_CODE_USE_GATEWAY environment variable began forcing Cloud-gateway sign-in on its own in 2.1.265 — even for teams using direct API keys or custom auth headers — producing "Not signed in to the Cloud gateway" errors. The 2.1.266 patch restores the previous behaviour: the variable is ignored unless accompanied by both ANTHROPIC_BASE_URL and ANTHROPIC_AUTH_TOKEN. Teams on self-hosted or proxied setups should upgrade to 2.1.266 immediately; teams on the default cloud path are unaffected.

# ~/.claude/settings.json — new folder-based plugin config
{
  "plugins": [
    "./plugins/engineering-team",   // auto-detects all manifests in folder
    "./plugins/data-science-team"
  ]
}

🧭 Anthropic IPO Prospectus Delayed — Public S-1 Now Expected Late September, Roadshow Shifts to Mid-October

When Anthropic confirmed its confidential S-1 filing with the SEC in June 2026, the widely-reported expectation was that the public prospectus would drop the week after US Labor Day (around September 8). That timeline has now slipped. As of September 9, the public prospectus is expected in late September, the investor roadshow has shifted to mid-October, and the exchange listing is targeting days before the US midterm elections in November — a tighter window than initially anticipated.

What the revised timeline means

• IPO quiet period continues: Anthropic remains under SEC quiet-period constraints, limiting what executives can say publicly about the business. This explains the relative silence from leadership on revenue, valuation, and forward guidance at a time when the industry would normally expect more visibility.
• Mid-October roadshow: Institutional roadshows typically last two to three weeks, putting the earliest possible listing in early November — ahead of midterms, which historically create market volatility and deter large issuances.
• No public prospectus yet: Until the S-1 is public, the valuation, revenue, and ownership figures widely cited in the press (including the frequently quoted $61.5 billion valuation from earlier funding rounds) are estimates, not verified figures. ClaudeBeat's editorial policy is to label them as such.
• Competitive context: The delay puts Anthropic's listing close to what some analysts describe as a congested autumn IPO window, given other large tech issuances in the pipeline. Whether Anthropic accelerates or holds to the November target will depend partly on market conditions in October.