thirdkeyai/symbi-claude-code/symbi-policy

Cedar policies

First determine whether the policy governs standalone plugin hooks or managed runtime tools. They use different action namespaces and contexts. Inspect the shipping request contract before using identity attributes or approvals.

Standalone plugin contract

The CLI receives tool_name and complete tool_input, and constructs:

• principal: Symbi::Agent::"claude-code" (fixed by this CLI, including Cursor)
• action: Symbi::Action::"tool_call::<native tool name>"
• resource: Symbi::Resource::"default"
• context: { "tool_input": <original arguments> }

For example, permit direct reads and content searches while leaving other calls denied by default:

permit(principal, action == Symbi::Action::"tool_call::Read", resource);
permit(principal, action == Symbi::Action::"tool_call::Grep", resource);

Claude Code shell calls use Bash; Cursor shell calls use Shell. This fixed principal is not a verified user identity. Local exceptions do not bypass Cedar.

Validate with complete representative payloads, including denied controls:

printf '%s\n' '{"tool_name":"Read","tool_input":{"file_path":"README.md"}}' |
  symbi policy evaluate --stdin --json --policies /absolute/policies

Inspect the structured decision and reason. Exit zero alone does not establish successful policy loading: the current runtime can return default allow when built without Cedar or with no policies; the plugin rejects those results. Do not use an empty {} event as evidence that a real request is permitted.

Managed runtime

Start from the policies generated by the chosen runtime profile. The managed CLI example uses Action::"tool_call::claude_code" for admission and exact tool names for brokered calls. File roots, approval and budget checks are additional runtime controls; a Cedar permit does not replace them.

Draft changes for operator review outside active policy directories. Do not modify an active control file or use shell execution to circumvent a denied write. Evaluate both allowed and forbidden representative requests before applying changes.