trace

Provides a user-friendly trace stack into an operation that occurred in Spice. This command retrieves and displays task execution traces from the runtime.task_history table.

Usage

spice trace [task] [flags]

task - The name of the task whose trace is requested. Supported tasks include:

• acceleration_refresh
• ai
• ai_chat
• ai_completion
• eval_run
• sql_query
• nsql
• text_embed
• tool_use::search
• tool_use::list_datasets
• tool_use::sql
• tool_use::table_schema
• tool_use::sample_data
• tool_use::load_memory
• tool_use::store_memory
• search
• scheduled_worker

Tools proxied from MCP servers and custom tools are recorded dynamically as tool_use::<tool>. Any such tool_use::-prefixed task name can be traced, not just the built-in tools listed above.

A tool that belongs to a non-default tool catalog — which includes every tool proxied from an MCP server — is exposed under a catalog-qualified name joining the catalog and the tool with __, for example github__search_code. That is the name /v1/tools lists and the name POST /v1/tools/{name} expects.

Every entry point records the same task name — tool_use:: followed by that exposed name, for example tool_use::github__search_code — whether the call arrives through the /v1/mcp gateway, through POST /v1/tools/github__search_code, or from a model deciding to use the tool. Grouping runtime.task_history by task therefore counts a tool once, and one spice trace tool_use::github__search_code sees every call to it.

Rows an older runtime wrote use a / separator

Runtimes up to and including v2.2.0 recorded a model-driven or POST /v1/tools/{name} call under tool_use::<catalog>/<tool> (tool_use::github/search_code) while the /v1/mcp gateway used the exposed __ name, so one tool's history was split across two task names. spice trace matches the task name exactly and still accepts the / spelling, so trace it as well to read history those runtimes wrote.

These tasks are from the task column in the Spice SQL runtime.task_history table.

Flags

• --trace-id Retrieve the trace with the given trace ID (the column trace_id from runtime.task_history).
• --id Retrieve the trace with the given id label (i.e. the task has a valid id within the labels column of runtime.task_history).
• --api-key Specify the API key for authentication.
• --include-output: Include, as an additional column, the captured output to each span (i.e. the captured_output column from runtime.task_history). Note: If captured outputs are not being stored, this will return an empty row.
• --include-input: Include, as an additional column, the input to each span (i.e. the input column from runtime.task_history).
• --truncate [<length>] Truncate the input and captured_output columns to the given number of characters. Defaults to 80 characters when the flag is passed without a value; when omitted, the columns are not truncated.
• -o, --output <format> Output format: table (default) or json.

The latest trace for the task will be used if neither --trace-id nor --id is specified.

Examples

Retrieve the trace for the last text-to-SQL operation

spice trace nsql

Retrieve the trace for a specific task by ID

spice trace ai_chat --id chatcmpl-At6ZmDE8iAYRPeuQLA0FLlWxGKNnM

Retrieve a trace by trace-id

spice trace sql_query --trace-id d5c6f1eed9f27257

Output Example

TREE                   STATUS DURATION   TASK
a97f52ccd7687e64       ✅       673.14ms ai_chat
  ├── 4eebde7b04321803 ✅         0.04ms tool_use::list_datasets
  └── 4c9049e1bf1c3500 ✅       671.91ms ai_completion

This output represents a structured trace of executed tasks.

Output Example (with --include-output)

TREE                   STATUS DURATION   TASK                    OUTPUT
a97f52ccd7687e64       ✅       673.14ms ai_chat                 The capital of New York is Albany.
  ├── 4eebde7b04321803 ✅         0.04ms tool_use::list_datasets []
  └── 4c9049e1bf1c3500 ✅       671.91ms ai_completion           [{"content":"The capital of New York is Albany.","refusal":null,"tool_calls":null,"role":"assistant","function_call":null,"audio":null}]