Did Anthropic change the prompt cache TTL?

Yes. In early March 2026, Anthropic's prompt-cache default TTL dropped from 1 hour to 5 minutes without a release note. This significantly increased costs for OpenClaw operators.

How does the prompt cache TTL change affect OpenClaw costs?

Operators who built context assuming a 1-hour cache now pay full token price on every gap longer than 5 minutes between messages. Cache writes cost 3.75 per million tokens while reads cost 0.375 per million, a 10x multiplier.

Is there a workaround for the 5-minute prompt cache TTL?

GitHub issue #62475 proposes keep-warm pings to prevent TTL expiry between turns. Users can also set cacheRetention to long for 1-hour TTL, but this requires explicit configuration.

Why did Anthropic reduce the prompt cache TTL?

Anthropic did not publish a release note explaining the change. It was likely a cost optimization on their end, shifting caching costs to heavy API users.

How do I configure prompt cache TTL in OpenClaw?

Set cacheControlTtl in the model params with options for 5m (short) or 1h (long). The default was silently changed to short (5 minutes) in March 2026.

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clawsmith.com/signal/anthropic-prompt-cache-ttl-5min-silent-cost-increase

⚠ IssueWide OpenLive

Anthropic Silently Drops Prompt Cache TTL From 1 Hour to 5 Minutes

Prompt-cache default TTL dropped from 1 hour to 5 minutes in March 2026 without release note. Operators pay full token price on sub-5-minute gaps.

Product Idea from this Signal

A background service that detects when AI providers silently change pricing, cache TTL, or access policies and automatically adjusts your OpenClaw config before your bill spikes

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Anthropic changed the prompt cache TTL from 1 hour to 5 minutes in March 2026 without a release note. Two weeks later they banned Claude subscriptions from OpenClaw entirely. Eighteen days after that they reversed the ban. Each policy change broke thousands of OpenClaw setups and spiked costs up to 50x. Operators have no automated way to detect these silent changes or defend against them. This background service monitors provider endpoints for pricing diffs, auth policy changes, and TTL modifications, then auto-patches your OpenClaw provider config, rotates to backup models, and alerts you before your monthly bill explodes.

BACKGROUND-SERVICECOST-OPTIMIZATIONDEVTOOLOPEN-SOURCE

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