Document crush price flags in the casper cheatsheet

[alycda]

What

Adds the four --price-* flags to the model add example in tools/cheat/cheatsheets/personal/crush/casper, as placeholders, with a note on where the real numbers belong.

Why

crush computes session cost only from per-model cost_per_1m_* rates (internal/agent/agent.go, updateSessionUsage). A custom provider with none set shows $0.00 forever, so casper needs prices supplied by hand.

Where the numbers live: only in the hand-managed ~/.config/crush/crushrc. If they are casper's internal rates, they stay out of this public repo entirely, agenix included. This follows the existing casper rule ("never committed, not even encrypted"). It also fits the mechanics: agenix decrypts at activation, but crush.json is built at eval time.

Naming trap, now recorded: --price-cache-create writes cost_per_1m_in_cached, which is billed against cache writes. --price-cache-hit writes cost_per_1m_out_cached, which is billed against cache reads, not output tokens.

Verification

• Flag names and JSON keys come from internal/shellconfig/model.go and the cost formula from agent.go, both on crush main at 76cc5c5 (2026-09-30). I have not checked them against the crush version charm-nur pins. Run model add with no arguments in your installed crush; the usage line lists the flags.
• The change is a cheatsheet comment only, with no Nix change, so lint and check are unaffected.

🤖 Generated with Claude Code

https://claude.ai/code/session_016D2WAsAGBJZHkbWegd613b

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Generated by Claude Code

[github-actions]

⊕ Entity-level changes

tools/cheat/cheatsheets/personal/crush/casper

Status	Type	Name
Δ	chunk	lines 1-20
-	chunk	lines 21-26
+	chunk	lines 21-37

Summary: 1 added, 1 modified, 1 deleted across 1 file

_{functions and classes, not lines · sem}