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

# Callback evidence

> Interpret anonymous callable ownership, static bindings, and the limits of caller tracing.

Use this reference when a caller trace includes lambdas or other anonymous callable bodies. Kast preserves their identity and reported ownership rather than treating every invocation as a call by the enclosing named function.

**A static path does not prove execution.** Supplying a lambda does not prove that it ran. Library callback activation and unsupported callback supplies remain explicit limits, even when other parts of the query are complete.

## Named callers and lexical ownership

`REFERENCES` reports lexical containment: a declaration-owned occurrence appears inside that declaration. This alone does not prove a named caller edge. `CALLERS` and `CALLEES` preserve `callback_observations` for invocations inside anonymous callable bodies. Each observation keeps the exact occurrence, lexical owner, anonymous body, and named-call policy. `EXCLUDED` explains why the invocation is absent from named callers; `ADMITTED_INLINE` keeps the separate anonymous owner even when the inline policy admits a named edge. `UNAVAILABLE` preserves incomplete ownership.

## Static bindings and unfinished proof

The observation's flow separates the supplied lambda's exact identity from its compiler-confirmed argument-to-parameter binding and the receiving function's exact parameter invocations. Those facts describe a possible static path. They do not claim that the callback ran. When a parameter invocation belongs to another lambda, `owner_bindings` retains that body’s exact supplying call and compiler-confirmed formal mapping where available. Those records retain `NESTED_CALLBACK_EXECUTION`: supplying a lambda does not prove its activation. Library mappings remain `EXTERNAL_CALLABLE` with the exact workspace supply and `OUTSIDE_DOMAIN`. A local initializer retains `STORED_CALLBACK`; a returned literal retains `RETURNED_CALLBACK`. Unsupported supply, including a direct literal invocation whose activation Kast cannot yet trace, retains `UNSUPPORTED_CALLBACK_SUPPLY`. Unresolved mapping, external body, or escaped parameter also retains an explicit obligation.

## Read the exact anonymous source

Inspect an exact source occurrence or anonymous body by passing its issued `candidateSelector` unchanged to `query_symbols`:

```json theme={null}
{
  "request": {
    "type": "READ_SOURCE",
    "candidateRef": "<issued candidateSelector>"
  }
}
```

This action uses the source-read owner and returns the exact anchored source with its authority and coverage. Reacquire the reference after an epoch change. Do not substitute the enclosing named function for the lambda.

## Continue output delivery

`page_progress` counts the current page's rows and evidence. A zero-row page can advance walk or callback evidence. Continue with the exact issued token and `next_action` until query output finishes; complete traversal coverage can precede complete output delivery.

See [Results](/reference/responses#follow-progress-not-row-count) for the difference between finishing query work and retrieving saved rows.


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