Ollama Python API error: llama-server response bufio.Scanner token too long

What this error means

bufio.Scanner: token too long (status code: -1) — Error from the python API: llama-server response is a Ollama failure pattern reported for developers trying to developers integrating ollama via python api get token-too-long errors when llama-server outputs responses exceeding bufio.scanner buffer limits, breaking llm pipeline processing. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Source: GitHub Issue #16243 on ollama/ollama (opened May 21, 2026, yesterday). Specific runtime error where llama-server response exceeds internal scanner buffer, returning status code -1. Concrete error signature with actionable fix path (configuring scanner buffer size or streaming response handling). Duplicate check vs covered-errors.md: no matching entry. Category: Ollama → Ollama local LLM serving.

Common causes

• Source: GitHub Issue #16243 on ollama/ollama (opened May 21, 2026, yesterday). Specific runtime error where llama-server response exceeds internal scanner buffer, returning status code -1. Concrete error signature with actionable fix path (configuring scanner buffer size or streaming response handling). Duplicate check vs covered-errors.md: no matching entry. Category: Ollama → Ollama local LLM serving.

Quick fixes

1. Confirm the exact error signature matches bufio.Scanner: token too long (status code: -1) — Error from the python API: llama-server response.
2. Check the Ollama account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/ollama/ollama/issues/16243

Evidence note: Source: GitHub Issue #16243 on ollama/ollama (opened May 21, 2026, yesterday). Specific runtime error where llama-server response exceeds internal scanner buffer, returning status code -1. Concrete error signature with actionable fix path (configuring scanner buffer size or streaming response handling). Duplicate check vs covered-errors.md: no matching entry. Category: Ollama → Ollama local LLM serving.

Related errors

• Ollama

FAQ

What should I check first?

Start with the exact bufio.Scanner: token too long (status code: -1) — Error from the python API: llama-server response text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Ollama workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without bufio.Scanner: token too long (status code: -1) — Error from the python API: llama-server response.