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Your Agent Is More Than the Model

Name: Your Agent Is More Than the Model
Price: 12.99 USD
Availability: InStock
Author: J Cook

The 7-Part Agent Harness for Swapping Models, Stretching Your Token Budget, and Shipping Working Code

eBook: $12.99 223 pages

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Fifteen minutes into the session the weekly quota is gone and the job never finished. Build the seven parts around the model that decide whether a job finishes: an adapter that swaps providers in one line, a token budget that holds, a claim checker, and an eval set that tests the next model the day it ships.

You open Codex. Fifteen minutes later the weekly quota is gone and the job never finished. Meanwhile someone on the same model, with the same limits, in the same week, is shipping. The difference is owning the loop the agent runs in instead of renting it.

This book does not teach you to build an agent. It teaches you to keep the one you already run when the model under it changes: a model adapter, a token budget, a state store, a claim checker, a routing table priced per finished job, an eval set built from your own work, and a stop that fires at the tool boundary instead of asking the model to please stop.

Every part ships in a free companion repository at the paths the book uses, with an offline test suite and an installer that wires the hooks for you.

What You'll Build

The Model Is 20 Percent. You Own the Rest.

Same model, different adapter, 54 points apart: the measured case for owning everything around the model.

Your Harness Already Exists. Here Is What It Owns.

Inventory the six layers of your current setup and mark each one yours, the vendor's, or nobody's.

Which Harness You Run, and What It Costs to Stay

Price leaving your current setup in hours, row by row, with a named input behind every hour.

One Job, Two Models, One Afternoon

Run one real job on two models and get your first measured figure for what the layer around the model is worth.

Make the Model a Part You Can Replace

Build a model adapter that changes providers in one line, then prove the same job passes on both.

The Tollgate: What You Pay Before the Model Reads a Word

Put a token budget with an eviction rule on one job and count the tokens before and after.

Keep the Work Outside the Conversation

Move run history into a state store so a long job stops paying for its own memory and resumes where it stopped.

Verify the Claim, Not the Code

Wire a claim checker on every completion that tests the contract, the exit code, and the bytes instead of the summary.

What One Finished Job Actually Costs

Price every finished job with the failed reruns counted in, then write a routing rule your setup reads.

Prove Which Combination Earns

Turn your own past commits into an eval set you run in one command the day a new model ships.

He Told It to Stop. It Deleted the Database Anyway.

Build a stop that fires at the tool boundary in both vendors, plus a failure-mode checklist with a drill for each row.

Eight Months, 883 Commits, Abandoned. Do This Instead.

A swap runbook and a thirty-day plan, so a new model launch costs one morning instead of a rebuild.

Free Articles from this Book

how-to

How to Get Claude Code to Finish the Job on the Cheaper Model

Get haiku finishing jobs you were paying sonnet to attempt, and quote what one finished job costs with the failures counted in. My first five runs finished nothing on either model; eleven words of job text later both went six for six.