Tool Gating

Tool gating controls which tools your agent is allowed to call during execution.

Configuration

policies:
  tools:
    allowed: [web_search, calculator, pdf_reader]
    deny_by_default: true

Fields (ToolPolicy)

Field	Type	Default	Description
`allowed`	`list[str]`	`[]`	Tool names the agent is permitted to use
`deny_by_default`	`bool`	`true`	When `true`, any tool not in `allowed` is blocked. When `false`, all tools are permitted.

How It Works

The is_tool_allowed() function (in both dockrion_policy/tool_guard.py and RuntimePolicyEngine):

if deny_by_default is false → allow all tools
if deny_by_default is true  → only allow tools in the allowed list

`deny_by_default`	`allowed` list	Tool “web_search”	Tool “send_email”
`true`	`[web_search, calculator]`	Allowed	Blocked
`true`	`[]` (empty)	Blocked	Blocked
`false`	`[web_search]`	Allowed	Allowed
`false`	`[]`	Allowed	Allowed

Usage Patterns

Strict allowlist (recommended for production)

policies:
  tools:
    allowed: [web_search, calculator, database_query]
    deny_by_default: true

Only the three listed tools can be called. Any other tool call is blocked.

No restrictions (development)

policies:
  tools:
    deny_by_default: false

All tools are allowed. Useful during development when you’re iterating on which tools the agent needs.

Block everything

policies:
  tools:
    allowed: []
    deny_by_default: true

No tools can be called. The agent can only use its own logic without external tool calls.

Integration with Frameworks

Tool gating is advisory — the runtime provides the is_tool_allowed() check, but enforcement depends on how the adapter/framework is configured:

LangGraph: Your graph can check is_tool_allowed() before executing tool nodes
Handler mode: Your handler function can call the policy engine to check tool permissions
Future: Automatic tool interception at the adapter level is planned

Source: ToolPolicy in packages/schema/dockrion_schema/dockfile_v1.py; is_tool_allowed() in packages/policy-engine/dockrion_policy/tool_guard.py

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