PabloThe agent runtime your application can own.

One bounded lifecycle for models, tools, policy, streaming, cancellation and traces—across a CLI, terminal, ACP and your Rust host.

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Read the architecture

pablo · ~/project

$pablo run "Map this repository." --no-shell

01run.startedtrace 7a93…

02tool.startedfs.list

03tool.finished42 entries · 3.1ms

04model.deltaI found two runtime crates…

completed 2 model calls · 1 tool call

PERFORMANCE / RUNTIME FOOTPRINT

Local runtime overhead, measured

On six synthetic non-coding knowledge-work tasks, Pablo had the lowest measured CPU utilization and peak process-tree memory of Pablo, Claude Code, Codex and Pi.

Bar charts comparing Pablo, Claude Code, Codex and Pi on peak process-tree memory and median CPU utilization. Pablo has the lowest measured value in both charts. — Exploratory single-seed pilot on macOS arm64. Models, provider routes, tools, reasoning settings and collection times differ.

Read the method, exact values and limitations →

One runtime lifecycle

Model calls, tools, child work, native events and OpenTelemetry settle together. Cancellation waits for owned cleanup.

Host-owned authority

Your application chooses the workspace, tools, credentials, policy, limits and approval experience.

Open interfaces

Run from a terminal, speak stable ACP over stdio, attach MCP tools, load Agent Skills or embed the Rust core.

prerelease developmentRust 1.98.1ACP · MCP · A2A · OTelmacOS + Linux

A small runtime with hard edges

Pablo is the execution layer between your application and a model. It streams a task through a typed provider, exposes only the tools your host admits, and returns one native outcome with exact accounting. It does not take over your product’s state or permission model.

CLI + TUI

Run one task, emit a machine envelope, or work from a compact interactive terminal.

Explore the terminal →02

ACP host

Connect an editor or application over the stable Agent Client Protocol with streamed updates.

Integrate over stdio →03

Rust core

Inject a provider, tracer, event sink and cancellation token into the runtime directly.

Embed the runtime →04

Deployment

Compose model routes, tools, policy, output contracts and telemetry in inspectable TOML.

Configure a host →

From prompt to settled outcome

01Admitconfig + policy

→

02Streammodel + events

→

03Actbounded tools

→

04Settleoutcome + usage

Every admitted task ends as completed, cancelled, timed_out, policy_denied, limit_exceeded, or failed. Failure preserves delivery certainty, so a host can distinguish a request that was never sent from one a remote service may have received.

Built for composition

Model routingVercel, OpenRouter, Open Responses, ordered fallback and private reasoning continuation.

Local capabilitiesFilesystem reads, revision-checked mutations and shell commands under explicit policy.

Open extensionsMCP tools, portable Agent Skills, supervised local children and remote A2A tasks.

Output contractsMachine envelopes, local JSON Schema validation and one bounded repair attempt.

OperationsOffline config inspection, focused diagnostics, bounded JSONL traces and OTLP export.

Prerelease status

Pablo is currently 0.1.0-dev.1 and must be built from source. Release archives, installers, signing limits and the full four-platform acceptance matrix are still in progress. The current runtime contract is intentionally versioned and may change before 0.1.

READY TO TRACE A REAL TASK?

Build the binary. Run the offline demo. Add a provider when you’re ready.

Get started in five minutes →