an engineer's home.

Building a Local-First Agent Framework in Rust (Part 16): Approval: Gating Tool Calls

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 16: Approval: Gating Tool Calls By the end of Chapter 15, the agent could remember notes across runs. It could call tools, write event logs, keep sessions on disk, and

Building a Local-First Agent Framework in Rust (Part 15): Memory Tiers: Notes

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 15: Memory Tiers: Notes Chapter 14 gave the agent run an audit trail. Every run can now leave an events.jsonl file inside its session directory. That file is about

Building a Local-First Agent Framework in Rust (Part 14): Recording the Loop

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 14: Recording the Loop: Events as JSONL Chapter 13 gave each run a place to live. A session now has a creation time, an id, and a directory under .abcb/

Building a Local-First Agent Framework in Rust (Part 13): Time, Identity, and Sessions on Disk

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 13: Time, Identity, and Sessions on Disk So far, a session has mostly been a conversation container. It held an id and a list of messages, but the id was

Building a Local-First Agent Framework in Rust (Part 12): Health Checks, doctor, and Testing HTTP

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 12: Health Checks, doctor, and Testing HTTP In the previous chapter, abcb crossed an important line. The provider stopped being only an in-process mock and became something that could

Building a Local-First Agent Framework in Rust (Part 11): Going Async and Over HTTP

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 11: Going Async and Over HTTP Until now, abcb has been living in a controlled room. The provider was a mock. It returned scripted strings from memory. That was not

Building a Local-First Agent Framework in Rust (Part 10): Configuration With TOML

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 10: Configuration With TOML So far, abcb has been mostly self-contained. The mock provider lives in the process. The default notes file is hardcoded. The loop step limit is

Building a Local-First Agent Framework in Rust (Part 9): Failing Gracefully With Recovery

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 9: Failing Gracefully With Recovery Chapter 8 gave abcb a loop. The framework could create a session, send it to the provider, parse the model's structured output, execute

Building a Local-First Agent Framework in Rust (Part 8): The Agent Loop and Session Continuity

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 8: The Agent Loop and Session Continuity Chapter 7 gave abcb one clean step. The framework could ask the provider for one assistant message, parse that message as ModelOutput, and

Building a Local-First Agent Framework in Rust (Part 7): The Model's Envelope and One Step

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 7: The Model's Envelope and One Step Chapter 6 gave abcb a set of capabilities. A tool can have a name, a description, and an implementation. The framework

Building a Local-First Agent Framework in Rust (Part 6): Tools and the Registry

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 6: Tools and the Registry Chapter 5 gave abcb a way to record what happened. That was not a feature that made the model smarter, but it changed the framework&

Building a Local-First Agent Framework in Rust (Part 5): Recording What Happened With an Event Log

See Part 0 for the latest table of contents and sample code. New chapters will be added over time. Chapter 5: Recording What Happened With an Event Log At the end of the previous chapter, abcb could run one mocked model turn. A user message went into a temporary session,