Claude Code startup context by model and settings

Tokens in the context window before the first message, from claude -p /context

What each setting saves

Tokens removed from the startup context by adding one setting from the user settings.json to a run with no settings: claude -p /context --setting-sources "" --settings '{…}'

Settings that change 100 tokens or less (the /context rounding step) are left out.

Price of the simplest request

API list price of claude -p hi, sent twice per configuration: the first call writes the prompt cache, the repeat reads it

Input includes everything Claude Code adds at runtime (environment, git status, …), so it is larger than the /context numbers above. Each run appends a random nonce to the system prompt so the first call never reuses an older cache.