Claude Code on a custom API gateway: what one turn actually costs

1 hour ago

Claude Code talks to whatever ANTHROPIC_BASE_URL points at. Point it at a gateway and the tool, the models and the workflow stay the same. Only the bill changes.

Shell

Code:

export ANTHROPIC_BASE_URL="https://api.uplinkswitch.com/v1"

export ANTHROPIC_AUTH_TOKEN="sk-uplink-live-..."

claude

Set ANTHROPIC_AUTH_TOKEN or ANTHROPIC_API_KEY, not both.

Or keep it in ~/.claude/settings.json

Code:

{

  "env": {

    "ANTHROPIC_BASE_URL": "https://api.uplinkswitch.com/v1",

    "ANTHROPIC_AUTH_TOKEN": "sk-uplink-live-...",

    "ANTHROPIC_DEFAULT_OPUS_MODEL": "claude-opus-5-5",

    "ANTHROPIC_DEFAULT_SONNET_MODEL": "claude-sonnet-5-5",

    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-5-5"

  }

}

Check the key before you start: curl https://api.uplinkswitch.com/v1/models -H "x-api-key: $ANTHROPIC_AUTH_TOKEN"

What one turn costs
I recorded one real turn on 2026-10-16: Sonnet 5.5, "add type hints and a docstring to slugify.py", 4 requests, 64 seconds. It cost $0.0551. The same tokens at Anthropic's list price: $0.0981.

Claude Opus 5.5: $2.10 / $6 per million tokens (list $4 / $20)
Claude Sonnet 5.5: $1.20 / $3 (list $2 / $10)
Claude Haiku 5.5: $0.06 / $0.15 (list $0.10 / $0.50)

To go back to your normal login: unset ANTHROPIC_BASE_URL ANTHROPIC_AUTH_TOKEN. Longer breakdown with cached tokens: what Claude Code costs on API billing.