diff --git a/models/xai/grok-4.20-0309-non-reasoning.yaml b/models/xai/grok-4.20-0309-non-reasoning.yaml
new file mode 100644
index 0000000..ea8fc59
--- /dev/null
+++ b/models/xai/grok-4.20-0309-non-reasoning.yaml
@@ -0,0 +1,52 @@
+# yaml-language-server: $schema=https://modelparams.dev/api/v1/schema.json
+provider: xai
+authType: api_key
+model: grok-4.20-0309-non-reasoning
+params:
+  - path: max_completion_tokens
+    type: integer
+    label: Max completion tokens
+    description: Upper bound for visible output tokens generated in the chat completion.
+    range:
+      min: 1
+    group: generation_length
+  - path: temperature
+    type: number
+    label: Temperature
+    description: Controls randomness. Lower values make outputs more focused; higher values make them more varied.
+    default: 1
+    range:
+      min: 0
+      max: 2
+      step: 0.1
+    group: sampling
+  - path: top_p
+    type: number
+    label: Top P
+    description: Controls nucleus sampling by limiting generation to tokens within the selected cumulative probability.
+    default: 1
+    range:
+      min: 0
+      max: 1
+      step: 0.01
+    group: sampling
+  - path: seed
+    type: integer
+    label: Seed
+    description: Optional seed used for decoding when reproducible sampling is desired.
+    group: sampling
+  - path: stop
+    type: string
+    label: Stop sequence
+    description: Stops generation when this sequence is produced. xAI accepts up to four stop sequences.
+    group: generation_length
+  - path: response_format.type
+    type: enum
+    label: Response format
+    description: Controls whether the model returns text, JSON mode output, or structured JSON schema output.
+    default: text
+    values:
+      - text
+      - json_object
+      - json_schema
+    group: output_format
diff --git a/models/xai/grok-4.20-0309-reasoning.yaml b/models/xai/grok-4.20-0309-reasoning.yaml
new file mode 100644
index 0000000..d086c8a
--- /dev/null
+++ b/models/xai/grok-4.20-0309-reasoning.yaml
@@ -0,0 +1,47 @@
+# yaml-language-server: $schema=https://modelparams.dev/api/v1/schema.json
+provider: xai
+authType: api_key
+model: grok-4.20-0309-reasoning
+params:
+  - path: max_completion_tokens
+    type: integer
+    label: Max completion tokens
+    description: Upper bound for visible output tokens generated in the chat completion.
+    range:
+      min: 1
+    group: generation_length
+  - path: temperature
+    type: number
+    label: Temperature
+    description: Controls randomness. Lower values make outputs more focused; higher values make them more varied.
+    default: 1
+    range:
+      min: 0
+      max: 2
+      step: 0.1
+    group: sampling
+  - path: top_p
+    type: number
+    label: Top P
+    description: Controls nucleus sampling by limiting generation to tokens within the selected cumulative probability.
+    default: 1
+    range:
+      min: 0
+      max: 1
+      step: 0.01
+    group: sampling
+  - path: seed
+    type: integer
+    label: Seed
+    description: Optional seed used for decoding when reproducible sampling is desired.
+    group: sampling
+  - path: response_format.type
+    type: enum
+    label: Response format
+    description: Controls whether the model returns text, JSON mode output, or structured JSON schema output.
+    default: text
+    values:
+      - text
+      - json_object
+      - json_schema
+    group: output_format
diff --git a/models/xai/grok-4.20-multi-agent-0309.yaml b/models/xai/grok-4.20-multi-agent-0309.yaml
new file mode 100644
index 0000000..d7b1322
--- /dev/null
+++ b/models/xai/grok-4.20-multi-agent-0309.yaml
@@ -0,0 +1,52 @@
+# yaml-language-server: $schema=https://modelparams.dev/api/v1/schema.json
+provider: xai
+authType: api_key
+model: grok-4.20-multi-agent-0309
+params:
+  - path: max_output_tokens
+    type: integer
+    label: Max output tokens
+    description: Upper bound for output tokens generated in the Responses API response.
+    range:
+      min: 1
+    group: generation_length
+  - path: temperature
+    type: number
+    label: Temperature
+    description: Controls randomness. Lower values make outputs more focused; higher values make them more varied.
+    default: 0.7
+    range:
+      min: 0
+      max: 2
+      step: 0.1
+    group: sampling
+  - path: top_p
+    type: number
+    label: Top P
+    description: Controls nucleus sampling by limiting generation to tokens within the selected cumulative probability.
+    default: 0.95
+    range:
+      min: 0
+      max: 1
+      step: 0.01
+    group: sampling
+  - path: reasoning.effort
+    type: enum
+    label: Reasoning effort
+    description: Controls whether the Responses API request uses the 4-agent or 16-agent multi-agent setup.
+    values:
+      - low
+      - medium
+      - high
+      - xhigh
+    group: reasoning
+  - path: text.format.type
+    type: enum
+    label: Text format
+    description: Controls whether the Responses API returns free-form text, JSON mode output, or structured JSON schema output.
+    default: text
+    values:
+      - text
+      - json_object
+      - json_schema
+    group: output_format
diff --git a/models/xai/grok-4.3.yaml b/models/xai/grok-4.3.yaml
new file mode 100644
index 0000000..b2296f2
--- /dev/null
+++ b/models/xai/grok-4.3.yaml
@@ -0,0 +1,58 @@
+# yaml-language-server: $schema=https://modelparams.dev/api/v1/schema.json
+provider: xai
+authType: api_key
+model: grok-4.3
+params:
+  - path: max_completion_tokens
+    type: integer
+    label: Max completion tokens
+    description: Upper bound for visible output tokens generated in the chat completion.
+    range:
+      min: 1
+    group: generation_length
+  - path: temperature
+    type: number
+    label: Temperature
+    description: Controls randomness. Lower values make outputs more focused; higher values make them more varied.
+    default: 1
+    range:
+      min: 0
+      max: 2
+      step: 0.1
+    group: sampling
+  - path: top_p
+    type: number
+    label: Top P
+    description: Controls nucleus sampling by limiting generation to tokens within the selected cumulative probability.
+    default: 1
+    range:
+      min: 0
+      max: 1
+      step: 0.01
+    group: sampling
+  - path: seed
+    type: integer
+    label: Seed
+    description: Optional seed used for decoding when reproducible sampling is desired.
+    group: sampling
+  - path: reasoning_effort
+    type: enum
+    label: Reasoning effort
+    description: Controls how much reasoning Grok performs before responding. Set to none for non-reasoning requests.
+    default: low
+    values:
+      - none
+      - low
+      - medium
+      - high
+    group: reasoning
+  - path: response_format.type
+    type: enum
+    label: Response format
+    description: Controls whether the model returns text, JSON mode output, or structured JSON schema output.
+    default: text
+    values:
+      - text
+      - json_object
+      - json_schema
+    group: output_format
diff --git a/models/xai/grok-build-0.1.yaml b/models/xai/grok-build-0.1.yaml
new file mode 100644
index 0000000..13a85e8
--- /dev/null
+++ b/models/xai/grok-build-0.1.yaml
@@ -0,0 +1,47 @@
+# yaml-language-server: $schema=https://modelparams.dev/api/v1/schema.json
+provider: xai
+authType: api_key
+model: grok-build-0.1
+params:
+  - path: max_completion_tokens
+    type: integer
+    label: Max completion tokens
+    description: Upper bound for visible output tokens generated in the chat completion.
+    range:
+      min: 1
+    group: generation_length
+  - path: temperature
+    type: number
+    label: Temperature
+    description: Controls randomness. Lower values make outputs more focused; higher values make them more varied.
+    default: 1
+    range:
+      min: 0
+      max: 2
+      step: 0.1
+    group: sampling
+  - path: top_p
+    type: number
+    label: Top P
+    description: Controls nucleus sampling by limiting generation to tokens within the selected cumulative probability.
+    default: 1
+    range:
+      min: 0
+      max: 1
+      step: 0.01
+    group: sampling
+  - path: seed
+    type: integer
+    label: Seed
+    description: Optional seed used for decoding when reproducible sampling is desired.
+    group: sampling
+  - path: response_format.type
+    type: enum
+    label: Response format
+    description: Controls whether the model returns text, JSON mode output, or structured JSON schema output.
+    default: text
+    values:
+      - text
+      - json_object
+      - json_schema
+    group: output_format
diff --git a/src/data/display.ts b/src/data/display.ts
index 703bfb6..bbf2e55 100644
--- a/src/data/display.ts
+++ b/src/data/display.ts
@@ -5,6 +5,7 @@ const PROVIDER_LABELS: Record<string, string> = {
   openai: "OpenAI",
   google: "Google",
   "x-ai": "xAI",
+  xai: "xAI",
   meta: "Meta",
   mistral: "Mistral",
   deepseek: "DeepSeek",
diff --git a/tests/catalog.test.ts b/tests/catalog.test.ts
index 2a31be7..29b9474 100644
--- a/tests/catalog.test.ts
+++ b/tests/catalog.test.ts
@@ -74,6 +74,7 @@ describe("display helpers", () => {
   it("knows the canonical provider names", () => {
     expect(providerLabel("anthropic")).toBe("Anthropic");
     expect(providerLabel("openai")).toBe("OpenAI");
+    expect(providerLabel("xai")).toBe("xAI");
   });
 
   it("uses overrides for known model display names", () => {