Fetch a trace's complete event tree showing spans, tool calls, LLM calls, guard triggers, and errors. Read-only inspection for troubleshooting agent runs.
Read-only full event tree for one retained trace. Shows spans, tool calls, LLM calls, guard triggers, and errors. Does not enforce BudgetGuard or intercept provider calls.
| Name | Required | Description | Default |
|---|---|---|---|
| trace_id | Yes | The trace ID to look up |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, open-world, and non-destructive behavior, so the description adds value beyond them by enumerating the event types returned and explicitly negating BudgetGuard enforcement and provider-call interception. No behavioral surprises remain undisclosed.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two tightly packed sentences lead with the read-only scope and core output, then list return contents and end with an important non-behavior. There is no filler or repetition of annotation metadata.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple one-parameter read tool with rich annotations, the description covers what the tool returns and what side effects it avoids. The absence of an output schema is acceptable because the description enumerates the event categories the returned tree contains.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% and the only parameter, trace_id, is already described as 'The trace ID to look up'. The description reinforces that it targets a single retained trace but does not add format, source, or lookup semantics beyond the schema, so the baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb (get) and resource (one retained trace), and describes the output as a 'full event tree' that includes spans, tool calls, LLM calls, guard triggers, and errors. This clearly differentiates it from the sibling tools, which target listings, decisions, alerts, usage, costs, or budget checks.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives clear context: use this for read-only inspection of a single retained trace and the full event tree. It also states exclusions ('does not enforce BudgetGuard or intercept provider calls'), helping an agent avoid expecting side effects, though it does not explicitly name sibling alternatives or when-not conditions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.