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# Module tool

> Managed and manual tool calls.

Generated from `cargo doc --no-deps -p nemo-relay-builtins -p nemo-relay-diagnostics -p nemo-relay-logging -p nemo-relay-plugin-host -p nemo-relay-codecs -p nemo-relay -p nemo-relay-runtime -p nemo-relay-model-pricing -p nemo-relay-resource-metrics -p nemo-relay-observability -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`.

Managed and manual tool calls.

## Structs

* [ToolAttributes](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolattributes): Bitflags that modify tool-call behavior and observability.
* [ToolCallEndParams](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolcallendparams): Builder parameters for [`tool_call_end`](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call-end).
* [ToolCallExecuteParams](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolcallexecuteparams): Builder parameters for [`tool_call_execute`](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call-execute).
* [ToolCallParams](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolcallparams): Builder parameters for [`tool_call`](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call).
* [ToolExecutionContext](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutioncontext): Transport-independent input supplied to a plugin tool execution interceptor.
* [ToolExecutionInterceptOutcome](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutioninterceptoutcome): Canonical result returned by a tool execution intercept.
* [ToolExecutionResult](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutionresult): Canonical application-visible result of tool execution.
* [ToolHandle](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolhandle): Runtime-owned handle identifying an active or completed tool call.

## Constants

* [TOOL_EXECUTION_INTERCEPT_OUTCOME_SCHEMA](/reference/api/rust-library-reference/nemo-relay/tool/constant-tool-execution-intercept-outcome-schema): Versioned native-plugin JSON envelope schema for [`ToolExecutionInterceptOutcome`](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutioninterceptoutcome).
* [TOOL_EXECUTION_RESULT_SCHEMA](/reference/api/rust-library-reference/nemo-relay/tool/constant-tool-execution-result-schema): Versioned native-plugin JSON envelope schema for [`ToolExecutionResult`](/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutionresult).

## Functions

* [tool_call](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call): Start a manual tool lifecycle span.
* [tool_call_end](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call-end): Finish a manual tool lifecycle span.
* [tool_call_execute](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call-execute): Execute a tool call through the managed middleware pipeline.
* [tool_conditional_execution](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-conditional-execution): Run only the tool conditional-execution guardrail chain.
* [tool_request_intercepts](/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-request-intercepts): Run only the tool request-intercept chain.

> Managed and manual tool calls.

## Docs

- [Struct Tool Attributes](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolattributes.md): Bitflags that modify tool-call behavior and observability.
- [Struct Tool Call EndParams](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolcallendparams.md): Builder parameters for `tool_call_end`.
- [Struct Tool Call Execute Params](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolcallexecuteparams.md): Builder parameters for `tool_call_execute`.
- [Struct Tool Call Params](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolcallparams.md): Builder parameters for `tool_call`.
- [Struct Tool Execution Context](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutioncontext.md): Transport-independent input supplied to a plugin tool execution interceptor.
- [Struct Tool Execution Intercept Outcome](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutioninterceptoutcome.md): Canonical result returned by a tool execution intercept.
- [Struct Tool Execution Result](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolexecutionresult.md): Canonical application-visible result of tool execution.
- [Struct Tool Handle](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/struct-toolhandle.md): Runtime-owned handle identifying an active or completed tool call.
- [Constant TOOL_EXECUTION_INTERCEPT_OUTCOME_SCHEMA](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/constant-tool-execution-intercept-outcome-schema.md): Versioned native-plugin JSON envelope schema for `ToolExecutionInterceptOutcome`.
- [Constant TOOL_EXECUTION_RESULT_SCHEMA](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/constant-tool-execution-result-schema.md): Versioned native-plugin JSON envelope schema for `ToolExecutionResult`.
- [Function tool_call](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call.md): Start a manual tool lifecycle span.
- [Function tool_call_end](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call-end.md): Finish a manual tool lifecycle span.
- [Function tool_call_execute](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-call-execute.md): Execute a tool call through the managed middleware pipeline.
- [Function tool_conditional_execution](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-conditional-execution.md): Run only the tool conditional-execution guardrail chain.
- [Function tool_request_intercepts](https://docs.nvidia.com/nemo/relay/dev/reference/api/rust-library-reference/nemo-relay/tool/fn-tool-request-intercepts.md): Run only the tool request-intercept chain.