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// SPDX-FileCopyrightText: Copyright (c) 2024-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
// SPDX-License-Identifier: Apache-2.0
use super::json::JsonParserType;
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct JsonParserConfig {
/// Start token for individual tool calls (e.g., `<TOOLCALL>`)
pub tool_call_start_tokens: Vec<String>,
/// End token for individual tool calls (e.g., `</TOOLCALL>`)
pub tool_call_end_tokens: Vec<String>,
/// Separator tokens between function name and arguments
/// (e.g., "<|tool▁sep|>" for DeepSeek v3.1)
/// Used by some models to separate function name from arguments
pub tool_call_separator_tokens: Vec<String>,
/// The key for the function name in the tool call
/// i.e. `{"name": "function", "arguments": {...}}` it would be
/// "name"
pub function_name_keys: Vec<String>,
/// The key for the arguments in the tool call
/// i.e. `{"name": "function", "arguments": {...}}` it would be
/// "arguments"
pub arguments_keys: Vec<String>,
/// The type of JSON parser to use
#[serde(default)]
pub parser_type: JsonParserType,
/// Parse input as bare JSON (a `{...}` object or `[...]` array) with no
/// wrapping markers. Intended for guided-decoding paths where the backend
/// emits a raw JSON shape. When true, `tool_call_start_tokens` /
/// `tool_call_end_tokens` are ignored.
#[serde(default)]
pub bare_json_mode: bool,
/// Allow recovery when the outer end-token is missing (max_tokens / EOS
/// truncation). Streaming jails MUST leave this `false` — otherwise the
/// parser claims "complete tool call" before the end-token has actually
/// arrived and `should_exit_jail_early` fires too aggressively. Finalize
/// / aggregate paths set it to `true` so a real but unterminated call
/// isn't silently dropped.
#[serde(default)]
pub allow_eof_recovery: bool,
}
impl Default for JsonParserConfig {
fn default() -> Self {
Self {
tool_call_start_tokens: vec!["<TOOLCALL>".to_string(), "<|python_tag|>".to_string()],
tool_call_end_tokens: vec!["</TOOLCALL>".to_string(), "".to_string()],
tool_call_separator_tokens: vec![],
function_name_keys: vec!["name".to_string()],
arguments_keys: vec!["arguments".to_string(), "parameters".to_string()],
parser_type: JsonParserType::Basic,
bare_json_mode: false,
allow_eof_recovery: false,
}
}
}
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct XmlParserConfig {
/// Start token for individual tool calls (e.g., "<tool_call>")
pub tool_call_start_token: String,
/// End token for individual tool calls (e.g., `</tool_call>`)
pub tool_call_end_token: String,
/// Start token for function name (e.g., `<function=`)
pub function_start_token: String,
/// End token for function (e.g., `</function>`)
pub function_end_token: String,
/// Start token for parameter (e.g., `<parameter=`)
pub parameter_start_token: String,
/// End token for parameter (e.g., `</parameter>`)
pub parameter_end_token: String,
/// See [`JsonParserConfig::allow_eof_recovery`]. Streaming jails MUST
/// leave this `false`.
#[serde(default)]
pub allow_eof_recovery: bool,
}
impl Default for XmlParserConfig {
fn default() -> Self {
Self {
tool_call_start_token: "<tool_call>".to_string(),
tool_call_end_token: "</tool_call>".to_string(),
function_start_token: "<function=".to_string(),
function_end_token: "</function>".to_string(),
parameter_start_token: "<parameter=".to_string(),
parameter_end_token: "</parameter>".to_string(),
allow_eof_recovery: false,
}
}
}
/// Configuration for DSML-style tool call parser (DeepSeek V3.2+)
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct DsmlParserConfig {
/// Start token for the DSML block (e.g., "<|DSML|function_calls>" or "<|DSML|tool_calls>")
#[serde(alias = "function_calls_start")]
pub block_start: String,
/// End token for the DSML block (e.g., "</|DSML|function_calls>" or "</|DSML|tool_calls>")
#[serde(alias = "function_calls_end")]
pub block_end: String,
/// Start prefix for invoke (e.g., "<|DSML|invoke name=")
pub invoke_start_prefix: String,
/// End token for invoke (e.g., "</|DSML|invoke>")
pub invoke_end: String,
/// Start prefix for parameter (e.g., "<|DSML|parameter name=")
pub parameter_prefix: String,
/// End token for parameter (e.g., "</|DSML|parameter>")
pub parameter_end: String,
}
impl Default for DsmlParserConfig {
fn default() -> Self {
Self {
block_start: "<|DSML|function_calls>".to_string(),
block_end: "</|DSML|function_calls>".to_string(),
invoke_start_prefix: "<|DSML|invoke name=".to_string(),
invoke_end: "</|DSML|invoke>".to_string(),
parameter_prefix: "<|DSML|parameter name=".to_string(),
parameter_end: "</|DSML|parameter>".to_string(),
}
}
}
/// Configuration for GLM-4.7 style tool call parser
/// Format: <tool_call>function_name<arg_key>param</arg_key><arg_value>value</arg_value></tool_call>
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct Glm47ParserConfig {
/// Start token for tool call block (e.g., "<tool_call>")
pub tool_call_start: String,
/// End token for tool call block (e.g., "</tool_call>")
pub tool_call_end: String,
/// Start token for argument key (e.g., "<arg_key>")
pub arg_key_start: String,
/// End token for argument key (e.g., "</arg_key>")
pub arg_key_end: String,
/// Start token for argument value (e.g., "<arg_value>")
pub arg_value_start: String,
/// End token for argument value (e.g., "</arg_value>")
pub arg_value_end: String,
/// See [`JsonParserConfig::allow_eof_recovery`]. Streaming jails MUST
/// leave this `false`.
#[serde(default)]
pub allow_eof_recovery: bool,
}
impl Default for Glm47ParserConfig {
fn default() -> Self {
Self {
tool_call_start: "<tool_call>".to_string(),
tool_call_end: "</tool_call>".to_string(),
arg_key_start: "<arg_key>".to_string(),
arg_key_end: "</arg_key>".to_string(),
arg_value_start: "<arg_value>".to_string(),
arg_value_end: "</arg_value>".to_string(),
allow_eof_recovery: false,
}
}
}
/// Configuration for Kimi K2 tool call parser
///
/// Format:
/// ```text
/// <|tool_calls_section_begin|>
/// <|tool_call_begin|>functions.{name}:{index}<|tool_call_argument_begin|>{json_args}<|tool_call_end|>
/// <|tool_calls_section_end|>
/// ```
///
/// The model may emit either plural or singular forms of section tokens
/// (e.g., `<|tool_calls_section_begin|>` or `<|tool_call_section_begin|>`).
/// Both forms are supported via the `section_start_variants` and `section_end_variants` fields.
/// See vllm `kimi_k2_tool_parser.py` for reference.
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct KimiK2ParserConfig {
/// Primary start token for the tool calls section
pub section_start: String,
/// Primary end token for the tool calls section
pub section_end: String,
/// All recognized start tokens for the tool calls section (includes singular variants)
pub section_start_variants: Vec<String>,
/// All recognized end tokens for the tool calls section (includes singular variants)
pub section_end_variants: Vec<String>,
/// Start token for an individual tool call (e.g., "<|tool_call_begin|>")
pub call_start: String,
/// End token for an individual tool call (e.g., "<|tool_call_end|>")
pub call_end: String,
/// Token separating function ID from JSON arguments (e.g., "<|tool_call_argument_begin|>")
pub argument_begin: String,
}
impl Default for KimiK2ParserConfig {
fn default() -> Self {
Self {
section_start: "<|tool_calls_section_begin|>".to_string(),
section_end: "<|tool_calls_section_end|>".to_string(),
section_start_variants: vec![
"<|tool_calls_section_begin|>".to_string(),
"<|tool_call_section_begin|>".to_string(),
],
section_end_variants: vec![
"<|tool_calls_section_end|>".to_string(),
"<|tool_call_section_end|>".to_string(),
],
call_start: "<|tool_call_begin|>".to_string(),
call_end: "<|tool_call_end|>".to_string(),
argument_begin: "<|tool_call_argument_begin|>".to_string(),
}
}
}
/// Parser-specific configuration
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
#[serde(tag = "type", rename_all = "snake_case")]
pub enum ParserConfig {
Json(JsonParserConfig),
Xml(XmlParserConfig),
Pythonic,
Harmony(JsonParserConfig),
Typescript,
Dsml(DsmlParserConfig),
KimiK2(KimiK2ParserConfig),
Glm47(Glm47ParserConfig),
/// Gemma 4 uses a custom non-JSON grammar with bare keys, `<|"|>` string
/// delimiters, and fixed `<|tool_call>...<tool_call|>` markers. No
/// configuration is required at runtime — markers are not user-tunable.
Gemma4,
}
impl ParserConfig {
/// Get the tool call start tokens for this parser configuration
/// Returns a vector of start tokens that indicate the beginning of a tool call
pub fn tool_call_start_tokens(&self) -> Vec<String> {
match self {
ParserConfig::Json(config) => config.tool_call_start_tokens.clone(),
ParserConfig::Harmony(config) => config.tool_call_start_tokens.clone(),
ParserConfig::Xml(config) => vec![config.tool_call_start_token.clone()],
ParserConfig::Pythonic => vec![],
ParserConfig::Typescript => vec![],
ParserConfig::Dsml(config) => vec![config.block_start.clone()],
ParserConfig::Glm47(config) => vec![config.tool_call_start.clone()],
ParserConfig::KimiK2(config) => config.section_start_variants.clone(),
ParserConfig::Gemma4 => vec![crate::tool_calling::gemma4::TOOL_CALL_START.to_string()],
}
}
/// Get the tool call end tokens for this parser configuration
/// Returns a vector of end tokens that indicate the end of a tool call
pub fn tool_call_end_tokens(&self) -> Vec<String> {
match self {
ParserConfig::Json(config) => config.tool_call_end_tokens.clone(),
ParserConfig::Harmony(config) => config.tool_call_end_tokens.clone(),
ParserConfig::Xml(config) => vec![config.tool_call_end_token.clone()],
ParserConfig::Pythonic => vec![],
ParserConfig::Typescript => vec![],
ParserConfig::Dsml(config) => vec![config.block_end.clone()],
ParserConfig::Glm47(config) => vec![config.tool_call_end.clone()],
ParserConfig::KimiK2(config) => config.section_end_variants.clone(),
ParserConfig::Gemma4 => vec![crate::tool_calling::gemma4::TOOL_CALL_END.to_string()],
}
}
}
/// Configuration for parsing tool calls with different formats
#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct ToolCallConfig {
/// Parser-specific configuration.
pub parser_config: ParserConfig,
}
impl Default for ToolCallConfig {
fn default() -> Self {
Self {
parser_config: ParserConfig::Json(JsonParserConfig::default()),
}
}
}
impl ToolCallConfig {
/// Default configuration for hermes tool calls
/// <tool_call>{"name": "get_weather", "arguments": {"location": "San Francisco, CA", "unit": "fahrenheit"}}\n</tool_call>
pub fn hermes() -> Self {
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["<tool_call>".to_string()],
tool_call_end_tokens: vec!["</tool_call>".to_string()],
..Default::default()
}),
}
}
/// Default configuration for nemotron tool calls
/// <TOOLCALL>[{"name": "get_weather", "arguments": {"location": "San Francisco, CA", "unit": "fahrenheit"}}]</TOOLCALL>
pub fn nemotron_deci() -> Self {
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["<TOOLCALL>".to_string()],
tool_call_end_tokens: vec!["</TOOLCALL>".to_string()],
..Default::default()
}),
}
}
pub fn llama3_json() -> Self {
// <|python_tag|>{ "name": "get_weather", "arguments": {"location": "San Francisco, CA", "unit": "fahrenheit"} }
// or { "name": "get_weather", "arguments": {"location": "San Francisco, CA", "unit": "fahrenheit"} }
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["<|python_tag|>".to_string()],
tool_call_end_tokens: vec!["".to_string()],
..Default::default()
}),
}
}
pub fn mistral() -> Self {
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["[TOOL_CALLS]".to_string()],
tool_call_end_tokens: vec!["[/TOOL_CALLS]".to_string(), "".to_string()],
..Default::default()
}),
}
}
pub fn phi4() -> Self {
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["functools".to_string()],
tool_call_end_tokens: vec!["".to_string()],
..Default::default()
}),
}
}
pub fn pythonic() -> Self {
Self {
parser_config: ParserConfig::Pythonic,
}
}
pub fn harmony() -> Self {
Self {
parser_config: ParserConfig::Harmony(JsonParserConfig {
tool_call_start_tokens: vec!["<|start|>assistant<|channel|>commentary".to_string()],
tool_call_end_tokens: vec!["<|call|>".to_string()],
..Default::default()
}),
}
}
pub fn deepseek_v3_1() -> Self {
// The whole tool calls block is wrapped between
// <|tool▁calls▁begin|> ... <|tool▁calls▁end|>
// regardless of number of tool calls. For external use of this
// config, we want them to only be operating on the whole block,
// so the tool parser can properly consume all tool call tokens.
// https://huggingface.co/deepseek-ai/DeepSeek-V3.1#toolcall
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec![
"<|tool▁calls▁begin|>".to_string(),
// "<|tool▁call▁begin|>".to_string(),
],
tool_call_end_tokens: vec![
"<|tool▁calls▁end|>".to_string(),
// "<|tool▁call▁end|>".to_string(),
],
tool_call_separator_tokens: vec!["<|tool▁sep|>".to_string()],
parser_type: JsonParserType::DeepseekV31,
..Default::default()
}),
}
}
pub fn deepseek_v3() -> Self {
// DeepSeek V3 format:
// <|tool▁calls▁begin|><|tool▁call▁begin|>{type}<|tool▁sep|>{function_name}\n```json\n{arguments}\n```<|tool▁call▁end|><|tool▁calls▁end|>
// There are some differences between DeepSeek V3 and DeepSeek V3.1
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["<|tool▁calls▁begin|>".to_string()],
tool_call_end_tokens: vec!["<|tool▁calls▁end|>".to_string()],
tool_call_separator_tokens: vec!["<|tool▁sep|>".to_string()],
parser_type: JsonParserType::DeepseekV3,
..Default::default()
}),
}
}
pub fn qwen3_coder() -> Self {
// <tool_call><function=name><parameter=key>value</parameter></function></tool_call>
Self {
parser_config: ParserConfig::Xml(XmlParserConfig::default()),
}
}
pub fn jamba() -> Self {
Self {
parser_config: ParserConfig::Json(JsonParserConfig {
tool_call_start_tokens: vec!["<tool_calls>".to_string()],
tool_call_end_tokens: vec!["</tool_calls>".to_string()],
..Default::default()
}),
}
}
fn deepseek_dsml(block_name: &str) -> Self {
Self {
parser_config: ParserConfig::Dsml(DsmlParserConfig {
block_start: format!("<|DSML|{}>", block_name),
block_end: format!("</|DSML|{}>", block_name),
..Default::default()
}),
}
}
pub fn deepseek_v3_2() -> Self {
// DeepSeek V3.2 format (DSML):
// <|DSML|function_calls>
// <|DSML|invoke name="function_name">
// <|DSML|parameter name="param_name" string="true|false">value</|DSML|parameter>
// </|DSML|invoke>
// </|DSML|function_calls>
Self::deepseek_dsml("function_calls")
}
pub fn deepseek_v4() -> Self {
// DeepSeek V4 format (DSML):
// <|DSML|tool_calls>
// <|DSML|invoke name="function_name">
// <|DSML|parameter name="param_name" string="true|false">value</|DSML|parameter>
// </|DSML|invoke>
// </|DSML|tool_calls>
Self::deepseek_dsml("tool_calls")
}
pub fn minimax_m2() -> Self {
// MiniMax-M2.1 format:
// <minimax:tool_call>
// <invoke name="function_name">
// <parameter name="param_name">value</parameter>
// </invoke>
// </minimax:tool_call>
// Reference: https://huggingface.co/MiniMaxAI/MiniMax-M2.1/blob/main/docs/tool_calling_guide.md
Self {
parser_config: ParserConfig::Xml(XmlParserConfig {
tool_call_start_token: "<minimax:tool_call>".to_string(),
tool_call_end_token: "</minimax:tool_call>".to_string(),
function_start_token: "<invoke name=".to_string(),
function_end_token: "</invoke>".to_string(),
parameter_start_token: "<parameter name=".to_string(),
parameter_end_token: "</parameter>".to_string(),
allow_eof_recovery: false,
}),
}
}
pub fn glm47() -> Self {
// GLM-4.7 format:
// <tool_call>function_name<arg_key>param1</arg_key><arg_value>value1</arg_value></tool_call>
// Reference: https://huggingface.co/zai-org/GLM-4.7/blob/main/chat_template.jinja
Self {
parser_config: ParserConfig::Glm47(Glm47ParserConfig::default()),
}
}
pub fn kimi_k2() -> Self {
// Kimi K2 format:
// <|tool_calls_section_begin|>
// <|tool_call_begin|>functions.{name}:{index}<|tool_call_argument_begin|>{json_args}<|tool_call_end|>
// <|tool_calls_section_end|>
// Reference: https://huggingface.co/moonshotai/Kimi-K2-Instruct/blob/main/docs/tool_call_guidance.md
Self {
parser_config: ParserConfig::KimiK2(KimiK2ParserConfig::default()),
}
}
/// Gemma 4 tool-call format (custom non-JSON grammar):
///
/// ```text
/// <|tool_call>call:func_name{location:<|"|>Tokyo<|"|>,count:42}<tool_call|>
/// ```
///
/// Bare unquoted keys, `<|"|>`-delimited strings, supports nested objects /
/// arrays. Multiple tool calls are concatenated without separators.
pub fn gemma4() -> Self {
Self {
parser_config: ParserConfig::Gemma4,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn dsml_config_deserializes_legacy_function_calls_aliases() {
let legacy = serde_json::json!({
"function_calls_start": "<|DSML|function_calls>",
"function_calls_end": "</|DSML|function_calls>",
"invoke_start_prefix": "<|DSML|invoke name=",
"invoke_end": "</|DSML|invoke>",
"parameter_prefix": "<|DSML|parameter name=",
"parameter_end": "</|DSML|parameter>",
});
let cfg: DsmlParserConfig = serde_json::from_value(legacy).unwrap();
assert_eq!(cfg.block_start, "<|DSML|function_calls>");
assert_eq!(cfg.block_end, "</|DSML|function_calls>");
assert_eq!(cfg.invoke_start_prefix, "<|DSML|invoke name=");
}
#[test]
fn deepseek_dsml_factory_produces_expected_block_tokens() {
let v3_2 = ToolCallConfig::deepseek_v3_2();
let v4 = ToolCallConfig::deepseek_v4();
let v3_2_cfg = match v3_2.parser_config {
ParserConfig::Dsml(c) => c,
_ => panic!("expected Dsml variant for v3_2"),
};
let v4_cfg = match v4.parser_config {
ParserConfig::Dsml(c) => c,
_ => panic!("expected Dsml variant for v4"),
};
assert_eq!(v3_2_cfg.block_start, "<|DSML|function_calls>");
assert_eq!(v3_2_cfg.block_end, "</|DSML|function_calls>");
assert_eq!(v4_cfg.block_start, "<|DSML|tool_calls>");
assert_eq!(v4_cfg.block_end, "</|DSML|tool_calls>");
}
}