The library

163 ways to spend fewer tokens

The 22 Beginner tips are free to read. The 141 advanced tactics unlock with Pro — plus a fresh tip in your inbox every morning.

🎚️Model Selection 60-80% on routed traffic

Stop Paying Frontier Prices for Boilerplate Work

Most of your token spend is on tasks a small model handles perfectly. Match the model to the job instead of defaulting to your most expensive option for everything.

Beginner 1 min Read →
🎚️Model Selection 🔒 Pro

Buy More Reasoning on the Cheap Model Before You Upgrade the Tier

When a cheap model stumbles on a hard task, the reflex is to jump to the frontier tier. Often the cheaper move is to keep the small model and turn its reasoning effort up — its per-token rate is so low it can brute-reason through the problem and still cost far less.

Intermediate 3 min Unlock →
🎚️Model Selection 🔒 Pro

Cascade: Try the Cheap Model First, Escalate Only When It Fails

Send every request to a small model first, programmatically check the answer, and only escalate to a frontier model when the cheap one falls short.

Intermediate 2 min Unlock →
🎚️Model Selection 🔒 Pro

Set service_tier flex for Batch Prices on the Sync Endpoint

Add a single parameter to your OpenAI Responses or Chat Completions calls to pay Batch-API rates without restructuring anything into async batch jobs. You keep a normal synchronous request/response flow and give up only guaranteed speed.

Intermediate 2 min Unlock →
🎚️Model Selection 🔒 Pro

Don't Burn Reasoning Tokens on Tasks That Don't Reason

Model selection isn't just which model — it's which reasoning mode. Turn thinking down or off for straightforward work and reserve deep reasoning for genuinely hard problems.

Intermediate 2 min Unlock →
🎚️Model Selection 🔒 Pro

The Harness Effect: Fix Your Orchestration Before You Reach for a Cheaper Model

The reflex when an agent bill climbs is to downgrade the model - a flat, one-time per-token discount that costs quality. A controlled study (The Harness Effect, arXiv 2607.06906) held the model fixed and changed only the orchestration layer, cutting tokens/task 38% and cost 41%. Audit and fix the harness - cache-shape, compaction, offload, suspend-don't-poll, failure governance - before you reach for a cheaper model.

Advanced 4 min Unlock →
🎚️Model Selection 🔒 Pro

Route a Step Down a Tier Only When the Saving Beats the Cache Rebuild

Complexity-aware routing backfires in long agent sessions if you ignore the prompt cache: switching models throws away the warm, model-scoped prefix, and the cold re-prefill can cost more than the frontier model would have for that one step. Make cache-rebuild cost a term in the routing decision.

Advanced 3 min Unlock →
🎚️Model Selection 🔒 Pro

Call the Critic Only When the Agent Is Unsure: Gate Verification on Action Uncertainty

A common reliability pattern for long-horizon agents is to run an expensive critic/verifier model after every step - which roughly doubles token spend even though most steps are unambiguous and gain nothing from a second opinion. Instead, read two cheap uncertainty signals from the actor's own next-action distribution - global entropy and the top-2 logit margin - to approximate the Value of Information of a critique, and invoke the critic only on the genuinely ambiguous steps. Let the actor internalize the critic's guidance over the run so the calls taper off as it improves.

Advanced 4 min Unlock →
🎚️Model Selection 🔒 Pro

Pin effort on the Managed Agents agent resource, not the session

In the Managed Agents API, an `effort` level set inside a per-session model override is silently ignored, and changing an agent's model `id` silently resets a pinned effort to the new model's default. Set effort on the agent resource, and re-assert it on every model swap.

Advanced 5 min Unlock →
🎚️Model Selection 🔒 Pro

Route Each Agent Step to a Model Tier, Not the Whole Run to the Frontier

A single agent trajectory mixes one hard planning step with a dozen trivial extraction steps, yet the reflex is to run every step on the frontier model. A tiny classifier can predict the smallest model tier that clears each step before you spend a token, using where the step sits in the run.

Advanced 3 min Unlock →
🎚️Model Selection 🔒 Pro

Score the Options, Don't Generate the Action: Offload Bounded Agent Decisions to a Tiny Classifier

Agent loops are full of tiny, bounded decisions with a fixed set of options: which action to take on a form field, whether a step is already done, which of N tools fits. Paying for a full generative LLM call on each is wasteful — a small discriminative model can score the fixed options instead, emitting zero tokens.

Advanced 2 min Unlock →
🎚️Model Selection 🔒 Pro

Retry Refusals Server-Side and Let Sticky Routing Stop You Re-Running the Doomed Model Every Turn

On a classifier-bearing model, a refusal-prone agent loop re-runs the primary and re-sends the whole thread every turn. Server-side fallback retries in one round trip, and sticky routing pins the conversation to the model that accepted so you stop paying for the doomed attempt.

Advanced 3 min Unlock →
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Use a Big Model as the Planner, Small Models as the Workers

In agentic and multi-step pipelines, reserve the frontier model for orchestration and hard reasoning, and delegate bulk subtasks (search, read, extract) to a cheaper model.

Advanced 2 min Unlock →

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