How to: Configure Permission Modes

Goal: Apply a PermissionMode preset and define PermissionRule patterns to control which tool operations the agent may perform.

PermissionMode presets

PermissionMode is Copy and Default (defaults to Default). It expresses a broad policy for the agent session:

#![allow(unused)]
fn main() {
use synwire_core::agents::permission::PermissionMode;

let mode = PermissionMode::Default;         // prompt for dangerous ops
let mode = PermissionMode::AcceptEdits;     // auto-approve file modifications
let mode = PermissionMode::PlanOnly;        // read-only, no mutations
let mode = PermissionMode::BypassAll;       // auto-approve everything (caution)
let mode = PermissionMode::DenyUnauthorized; // deny unless a pre-approved rule matches
}

PermissionRule

Rules match tool names using glob patterns and assign a PermissionBehavior:

#![allow(unused)]
fn main() {
use synwire_core::agents::permission::{PermissionBehavior, PermissionRule};

let rules = vec![
    // Allow all file reads without prompting.
    PermissionRule {
        tool_pattern: "read_file".to_string(),
        behavior: PermissionBehavior::Allow,
    },
    // Always ask before writing.
    PermissionRule {
        tool_pattern: "write_file".to_string(),
        behavior: PermissionBehavior::Ask,
    },
    // Block process spawning entirely.
    PermissionRule {
        tool_pattern: "spawn_background".to_string(),
        behavior: PermissionBehavior::Deny,
    },
    // Wildcard: allow all git operations.
    PermissionRule {
        tool_pattern: "git_*".to_string(),
        behavior: PermissionBehavior::Allow,
    },
];
}

PermissionBehavior values:

How rules interact with approval callbacks

Rules are evaluated before the operation reaches an approval gate:

1. The runner matches the tool name against all PermissionRule patterns in order.
2. On Deny — the operation is blocked immediately; the approval callback is not called.
3. On Allow — the operation proceeds; the approval callback is not called.
4. On Ask (or no matching rule) — the operation is forwarded to the ApprovalCallback (e.g. ThresholdGate).

Under DenyUnauthorized mode, any tool with no matching rule and no Ask result is blocked as if Deny were returned.

Under BypassAll mode, Ask results are treated as Allow — the approval callback is still invoked but the answer is ignored.

Serialisation

Both types derive Serialize and Deserialize, so rules can be loaded from a config file:

#![allow(unused)]
fn main() {
use synwire_core::agents::permission::{PermissionMode, PermissionRule};

let rules: Vec<PermissionRule> = serde_json::from_str(r#"[
    {"tool_pattern": "read_file", "behavior": "Allow"},
    {"tool_pattern": "write_file", "behavior": "Ask"},
    {"tool_pattern": "rm", "behavior": "Deny"}
]"#)?;

let mode: PermissionMode = serde_json::from_str(r#""AcceptEdits""#)?;
}

See also

• How to: Configure Approval Gates
• How to: Configure Signal Routing
• Explanation: Architecture