Free Allowances for AI Coding CLIs
Checked on 2026-09-12. A free login, a paid subscription allowance, API trial credit, and a temporary promotion are different things. Vendors can change all four without changing the CLI binary.
Short Answer: Is “Grok CLI” Free?
There is an official xAI terminal agent, now called Grok Build, and its command is grok. The official installer is:
curl -fsSL https://x.ai/cli/install.sh | bash
On first launch it can authenticate through an xAI account; XAI_API_KEY is the alternative for API-backed use. This should not be confused with unrelated third-party projects named grok-cli on GitHub.
The August 12, 2026 Grok 4.6 announcement advertises “Try it in Grok Build for free” and 2× included usage for the first week. That is a dated launch offer, not a September allowance or a permanent free tier. The available Build documentation does not state a durable numerical free quota or reset schedule.
Verdict: confirm current account eligibility before relying on free access. The launch announcement supports a historical free-trial offer, not a verified free login today.
The ambiguity is not academic. Grok Build launched on 2026-05-25 as an early beta limited to SuperGrok and X Premium Plus subscribers. The 2026-08-12 page broadened the message to free trial access. Old posts that describe either state as permanent are already stale.
Current Comparison
What the Numbers Actually Count
The cleanest allowance here is Gemini's, but even it is not “1,000 prompts.” Google states that one prompt can trigger multiple model requests. The daily limit is shared between Gemini CLI and Gemini Code Assist agent mode and aggregated across model families. For practical planning, inspect consumption rather than counting terminal submissions.
Codex, Grok Build, and Copilot increasingly expose compute-weighted limits rather than a fixed message count. A long repository task, tool-heavy loop, or large context can consume much more allowance than a short question. A vendor dashboard is therefore the account-specific source of truth when public documentation gives only a qualitative tier.
Subscription routes and API-key routes must also remain separate:
- signing into Codex with ChatGPT uses the plan allowance shared with ChatGPT Work; an API key is billed separately by API tokens and lacks cloud-based features;
- signing into Claude Code with a paid Claude account uses shared subscription limits; CLI API keys follow the precedence rules below;
- signing into Grok Build may use included account usage;
XAI_API_KEYinvokes the priced xAI API route; - an open-source harness such as Qwen Code can be free to install while its selected model is local, free promotional, or paid.
Claude Code authentication differs by surface. In the CLI, an ANTHROPIC_API_KEY approved for interactive use takes precedence over subscription login and uses API billing. In non-interactive -p mode, a present key is used without that interactive approval. Cloud-provider or gateway credentials can take precedence over the key; check /status for the active route. Claude Code on the Web always uses subscription credentials, even if this variable is set in its sandbox.
Best Zero-Cost Starting Order
- Gemini CLI for the clearest published request allowance in this comparison.
- Codex CLI for a real free plan when a small, undisclosed allowance is acceptable.
- GitHub Copilot CLI if a GitHub account and automatic model selection fit the task; use the billing dashboard for the actual AI-credit balance.
- Grok Build only after confirming current trial eligibility. Run a small canary before depending on it.
- Open-source BYOK harnesses only after choosing the model endpoint; “free CLI” says nothing about inference cost.
Claude Code belongs in the comparison because it is a major terminal tool, but not in the zero-payment queue. Qwen Code's former OAuth quota should be removed from current recommendation lists.
Verification Checklist
Before starting work that must finish within a free allowance:
- Confirm the exact official product and executable.
- Record the authentication route: consumer login, subscription, API key, or local model.
- Open the provider's usage page or run the CLI's status command where available.
- Check the reset window and whether other products share the pool.
- Disable or remove API-key fallbacks if an accidental charge would be unacceptable.
- Use a disposable repository and a small task first; a successful login does not prove enough remaining capacity for an agent loop.
Update Rule
Recheck this note after 14 days, or immediately when a vendor changes plan names, authentication, or quota UI. Promote a number into the table only when an official source states its unit and reset period. Keep “not disclosed” rather than deriving a quota from anecdotes, frontend flags, or a single account's remaining balance.