phaseo-agent crate when a Rust application needs a bounded model loop, local tools, approvals, or resumable human review.
The Rust Agent SDK builds on the phaseo client and runs model turns through the Phaseo Responses API.
Supported capabilities
Rust is a supported synchronous runtime, not a feature-for-feature port of the TypeScript streaming runtime. The pages in this section document only APIs shipped in
phaseo-agent 0.1.Runtime model
Each run:- sends the current messages and tool definitions to a
ModelClient - executes available local tools
- pauses for approvals, external outputs, or human review when required
- appends results and continues until completion or the step limit
RunResult in your application when a run must survive a process restart.
The 0.1 Gateway adapter does not currently map Gateway cost_nanos or cost_cents into UsageSummary.cost. Use the Gateway response or generation record for spend reporting rather than the Agent SDK cost field.
Install the Agent SDK
Add both Rust crates and configure your API key.
Build your first agent
Run a local tool loop through Phaseo Gateway.
Tools and approvals
Add local, external, and approval-gated tools.
Agent API reference
Review the exact Rust structs, traits, and methods.