docs: add security reporting guidance

README.md

@@ -107,7 +107,8 @@ Learning from Human Feedback**).
 
 The **[CopilotKit Slack quickstart](https://docs.copilotkit.ai/slack)** is the canonical guide
 to building a Slack agent — read it alongside this starter. Detailed setup and configuration
-lives in **[setup.md](./setup.md)**.
+lives in **[setup.md](./setup.md)**. For token-handling and reporting guidance, see
+**[SECURITY.md](./SECURITY.md)**.
 
 ## License
 

SECURITY.md

@@ -0,0 +1,48 @@
+# Security policy
+
+OpenTag is a self-hosted chat agent that connects to Slack, model providers, and optional tools
+such as Linear, Notion, Redis, and WhatsApp. Treat the host running OpenTag as a trusted
+automation environment.
+
+## Supported versions
+
+OpenTag is currently distributed as source from this repository. Please file security reports
+against the current `main` branch unless a release branch is published.
+
+## Reporting a vulnerability
+
+Please report suspected vulnerabilities privately to the maintainers instead of opening a public
+issue with exploit details or credentials. Use GitHub private vulnerability reporting if it is
+enabled; otherwise use the maintainers' preferred private contact channel.
+
+When reporting, include:
+
+- A short description of the affected flow or file
+- Reproduction steps using placeholder credentials only
+- The expected impact
+- Any suggested mitigation
+
+Do **not** include real Slack tokens, model-provider keys, Linear keys, Notion tokens,
+Redis URLs with passwords, cookies, private keys, or production logs containing secrets.
+
+## Secret-handling checklist
+
+Before sharing logs, screenshots, issues, or pull requests:
+
+- Keep `.env`, `.env.local`, browser profiles, and `e2e/results/` out of git.
+- Redact values that start with `xoxb-`, `xapp-`, `sk-`, `sk-ant-`, `lin_api_`, or
+  provider-specific token prefixes.
+- Redact `Authorization` headers, cookies, webhook verification tokens, and Redis URLs that
+  include passwords.
+- Rotate any token that was pasted into a public issue, PR, screenshot, log, or chat transcript.
+- Use the example placeholders in `.env.example`; never copy production values into documentation.
+
+## Deployment guidance
+
+- Prefer Slack Socket Mode for local/self-hosted development so the bot does not require a public
+  inbound URL.
+- If exposing any endpoint publicly, put it behind HTTPS and the minimum required authentication.
+- Keep the agent runtime endpoint (`AGENT_URL`) private unless you intentionally protect it with an
+  auth layer.
+- Use least-privilege Slack scopes and reinstall the app after changing the manifest.
+- Treat MCP integrations as privileged tool execution paths; enable only the tools you need.