> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nano-gpt.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Model Suffixes

> Supported suffixes for web search, memory, PII redaction, caching, reasoning visibility, thinking variants, and provider routing preferences.

# Model Suffixes

Append supported suffixes to the `model` value to request optional behavior for a single request. Most suffixes are stripped before the base model is routed. Model identity suffixes, such as supported `:thinking` variants, are preserved because they identify a distinct model or alias.

Suffix parsing is case-insensitive for provider routing and provider suffixes. Avoid combining multiple suffixes that make conflicting provider-selection requests.

## Provider Routing Preference Suffixes

These apply only to provider-selection-capable models.

| Suffix        | Meaning                                                                                  |
| ------------- | ---------------------------------------------------------------------------------------- |
| `:speed`      | Pick the provider with the best estimated completion time, using TTFT plus TPS.          |
| `:fast`       | Alias for `:speed`.                                                                      |
| `:throughput` | Pick the provider with the highest tokens per second.                                    |
| `:latency`    | Pick the provider with the lowest time to first token.                                   |
| `:price`      | Pick the cheapest provider by base input-plus-output token price.                        |
| `:cheap`      | Alias for `:price`.                                                                      |
| `:floor`      | Alias for `:price`.                                                                      |
| `:tools`      | Route to a tools-capable provider path for models that support tools provider selection. |
| `:caching`    | Require routing to a cache-capable provider, equivalent to top-level `caching: true`.    |
| `:cache`      | Alias for `:caching`.                                                                    |
| `:cached`     | Alias for `:caching`.                                                                    |

```json theme={null}
{ "model": "zai-org/glm-5:fast", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "zai-org/glm-5:cheap", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "moonshotai/kimi-k2.6:thinking:caching", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "moonshotai/kimi-k2.6:tools", "messages": [{ "role": "user", "content": "Hello" }], "tools": [{ "type": "function", "function": { "name": "lookup", "parameters": { "type": "object", "properties": {} } } }] }
```

Rules:

* Routing preference suffixes only consider user-selectable providers. Internal routing-only providers are excluded.
* Routing preference suffixes are stripped before model mapping/routing. Non-routing identity suffixes such as `:thinking` are preserved.
* Do not combine `:speed`, `:fast`, `:throughput`, `:latency`, `:price`, `:cheap`, or `:floor` with `X-Provider`, body `provider`, or a provider model suffix.
* Do not combine `:tools` with a routing preference suffix, `X-Provider`, body `provider`, a provider model suffix, or `caching: true`.
* Do not combine `:caching`, `:cache`, or `:cached` with `:tools`, `X-Provider`, body `provider`, a provider model suffix, or another routing preference suffix.
* Routing preference requests are billed like explicit provider-selection requests.
* Conflict error codes use the existing `speed_suffix_*` family for API compatibility, even when the suffix is not literally `:speed`.

The caching suffixes are provider-capability routing, not prompt-cache annotation. They do not add Anthropic-style `cache_control` markers, configure cache TTLs, or force a cache write. For details, see [Prompt Caching](/api-reference/miscellaneous/prompt-caching#cache-capable-provider-routing).

## Provider Suffixes

The API accepts a trailing provider suffix for public user-selectable provider IDs:

```json theme={null}
{ "model": "zai-org/glm-5:cerebras", "messages": [{ "role": "user", "content": "Hello" }] }
```

Recommended: use `X-Provider` for explicit provider overrides. The API also accepts a trailing provider suffix for user-selectable providers, such as `model-id:cerebras`, but `X-Provider` is clearer and easier to validate against provider-discovery responses.

Provider suffixes must match a public user-selectable provider ID. They are case-insensitive, cannot be combined with routing preference suffixes or `:tools`, and are billed like explicit provider selection.

## Web Search Suffixes

| Suffix                       | Meaning                                                                                                                               |
| ---------------------------- | ------------------------------------------------------------------------------------------------------------------------------------- |
| `:online`                    | Default web search, standard depth. For GPT-5+ / o-series models this may use OpenAI native web search unless a provider is explicit. |
| `:online/linkup`             | Linkup standard.                                                                                                                      |
| `:online/linkup-deep`        | Linkup deep.                                                                                                                          |
| `:online/tavily`             | Tavily standard.                                                                                                                      |
| `:online/tavily-deep`        | Tavily deep.                                                                                                                          |
| `:online/brave`              | Brave standard.                                                                                                                       |
| `:online/brave-deep`         | Brave deep.                                                                                                                           |
| `:online/exa-fast`           | Exa fast.                                                                                                                             |
| `:online/exa-auto`           | Exa auto.                                                                                                                             |
| `:online/exa-neural`         | Exa neural.                                                                                                                           |
| `:online/exa-deep`           | Exa deep.                                                                                                                             |
| `:online/exa-deep-reasoning` | Exa deep-reasoning.                                                                                                                   |
| `:online/exa-instant`        | Exa instant.                                                                                                                          |
| `:online/kagi`               | Kagi standard search.                                                                                                                 |
| `:online/kagi-web`           | Kagi standard web.                                                                                                                    |
| `:online/kagi-news`          | Kagi standard news.                                                                                                                   |
| `:online/kagi-search`        | Kagi deep search.                                                                                                                     |
| `:online/perplexity`         | Perplexity standard.                                                                                                                  |
| `:online/perplexity-deep`    | Perplexity deep.                                                                                                                      |
| `:online/valyu`              | Valyu standard, all sources.                                                                                                          |
| `:online/valyu-deep`         | Valyu deep, all sources.                                                                                                              |
| `:online/valyu-web`          | Valyu standard, web only.                                                                                                             |
| `:online/valyu-web-deep`     | Valyu deep, web only.                                                                                                                 |

Web search suffixes can compose with memory and reasoning-exclude suffixes. If request body `webSearch.enabled` or legacy `linkup.enabled` is true, body configuration takes precedence over model suffix configuration.

## Memory Suffixes

| Suffix           | Meaning                                                      |
| ---------------- | ------------------------------------------------------------ |
| `:memory`        | Enable Context Memory with default 30-day retention.         |
| `:memory-<days>` | Enable Context Memory with retention clamped to 1..365 days. |

Header `memory_expiration_days` takes precedence over `:memory-<days>`. `memory: false` in the request body explicitly disables memory even if the model has a memory suffix. Memory can compose with web search, for example `openai/gpt-5.2:online:memory-90`.

## PII Redaction Suffixes

| Suffix          | Meaning                                |
| --------------- | -------------------------------------- |
| `:redaction`    | Enable PII redaction for this request. |
| `:redacted`     | Alias for `:redaction`.                |
| `:piiredaction` | Alias for `:redaction`.                |
| `:piiredacted`  | Alias for `:redaction`.                |

Redaction suffixes are stripped before model routing and can compose with other supported NanoGPT suffixes, such as `:online`. If a request explicitly enables redaction with a model suffix, redaction remains enabled even if an account-level or API-key default would otherwise be disabled for that request.

For details, pricing, and limitations, see [PII Redaction](/api-reference/miscellaneous/pii-redaction).

## Reasoning and Thinking Suffixes

| Suffix                                | Meaning                                                                                                             |
| ------------------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| `:thinking`                           | Model-specific thinking/reasoning variant when that exact ID or documented alias exists.                            |
| `-thinking`                           | Legacy alias pattern for some model families only, not universal.                                                   |
| `:<number>` on Anthropic thinking IDs | Thinking budget suffix for mapped Anthropic thinking aliases, for example `claude-sonnet-4-thinking:8192`.          |
| `:reasoning-exclude`                  | Equivalent to `reasoning: { "exclude": true }`; hides reasoning fields/blocks and strips the suffix before routing. |

`:reasoning-exclude` works on Chat Completions and Text Completions. It composes with other suffixes such as `:thinking`, `:online`, and `:memory`. `:thinking` is model identity, not provider routing, and is not universal.

## Official and Original Route Suffixes

Some model families expose `:official` / `:original` aliases to force the official-provider route. These are model-specific; check the model page or provider-selection docs for supported IDs.

## Conflict Rules

Do not combine conflicting routing directives:

```json theme={null}
{ "model": "zai-org/glm-5:fast:cerebras" }
{ "model": "zai-org/glm-5:cheap", "provider": "cerebras" }
{ "model": "zai-org/glm-5:tools:fast" }
```

## Examples

```json theme={null}
{ "model": "zai-org/glm-5:fast", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "zai-org/glm-5:cheap", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "zai-org/glm-5:thinking:fast", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "moonshotai/kimi-k2.6:thinking:caching", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "openai/gpt-5.2:online/exa-instant:memory-30", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "openai/gpt-5.2:redaction:online", "messages": [{ "role": "user", "content": "Hello" }] }
{ "model": "anthropic/claude-opus-4.6:memory-30:online/linkup-deep:reasoning-exclude", "messages": [{ "role": "user", "content": "Hello" }] }
```