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The journal

AI blog on models, prices and news

New models, their prices, what works and what is a waste of money.

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How to use multiple AI models in one place

Connect multiple AI models in one place with a multi-key BYOK app, the OpenRouter gateway or a developer layer, then compare them side by side.

Read the article → A locksmith showing a tray of keys to a customer in front of a key wallAI without a subscription12 min read

Which API key to choose for your real needs

Which API key to choose, with a grid by need, the budget, GDPR and speed constraints, every provider in two sentences and the test that really decides.

Read the article → A woman tasting a cheese sample offered by a vendor at a market stallAI without a subscription12 min read

How to try AI without a credit card

Try AI without a credit card through free chats and no-card API tiers, with the data trade-off and the fake free offers sorted out level by level.

Read the article → A tailor pinning a dark jacket on a dressmaker dummy in her studioAI without a subscription12 min read

Build a personal AI assistant with your own API key

Build a personal AI assistant with no code and no model subscription, using an API key, a five-block role, your own documents and steady weekly tuning.

Read the article → A man reading two restaurant chalkboards, a set menu and an a la carte listAI without a subscription11 min read

GPT-4o API vs ChatGPT Plus, what really changes

GPT-4o through the API and ChatGPT Plus are two products with two logics. The figures on both sides, a worked example both ways and how to start with a key.

Read the article → A woman hanging a house key on a wall hook near a doorwayAI without a subscription8 min read

Storing an API key in the browser safely

A publisher's key served to visitors never belongs in the browser, while your own BYOK key can live there safely. The line, the risks and the fixes.

Read the article → A smiling woman handing a labeled key from a key board to a colleagueAI without a subscription10 min read

How to share an API key with your team safely

The right way to share an API key with a team is one key per person through the provider's organization, plus a few channels you never use.

Read the article → A woman fitting a new cylinder into the lock of a wooden front doorAI without a subscription9 min read

Revoke and rotate an API key without downtime

Revoke, regenerate and rotate explained, with the two-key switchover that changes a key without downtime and a rotation rhythm you can actually keep.

Read the article → A man turning a red valve on the pipe under a sinkAI without a subscription9 min read

Leaked API key, the emergency procedure in five steps

A leaked API key calls for a fixed order. Revoke it in thirty seconds, create a new one, audit usage, close the source and set the cap.

Read the article → A man opening a small wall-mounted key safe in his workshopAI without a subscription8 min read

API key security in 8 practices that actually matter

Protect your API key with eight simple habits covering safe storage, one key per use, least privilege, rotation, a spending cap, monitoring and encrypted transfer.

Read the article → A woman writing down the reading of a wall meter in her notebookAI without a subscription11 min read

Track your API usage every day without a spreadsheet

Track your AI API usage on three levels, from the provider dashboard to dedicated observability and a homemade log. The useful metrics and the two-minute routine.

Read the article → A woman marking up printed pages with a red pencil at her deskAI without a subscription12 min read

Shorter prompts without losing answer quality

Shorten your prompts without hurting the answers. Seven moves ranked from safest to most technical, plus the ablation method that protects quality.

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