> ## 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.

# API and RPC reference

> Choose the right Kast contract before reading detailed callable and result schemas.

Kast has three agent-facing connections. They share the canonical operation
documents, but each connection has its own outer result. Start with the
contract for the connection you use.

| Connection              | Start here                                       | Discover the installed inputs         |
| ----------------------- | ------------------------------------------------ | ------------------------------------- |
| Direct MCP              | [MCP contract](/reference/mcp-catalog)           | `tools/list`                          |
| One-shot tool RPC       | [Tool RPC contract](/reference/rpc-catalog)      | `kast-tool-rpc-complete catalog`      |
| Hosted Codex App Server | [Callable schemas](/api-reference/query-symbols) | Provider catalog for the conversation |

## Read a result

[Read a Kast result](/reference/responses) explains the outer reply and the
canonical document together. A successful transport call can still contain a
qualified or rejected semantic result. Preserve exact `ref` values, scope,
coverage, and failure details when continuing a read.

For the common workflow, start with [Find Kotlin declarations](/search), then
[Compose a query](/query-pipelines). [Read a symbol](/reference/symbols)
explains the fields carried by one exact compiler result.

## Find a callable

| Callable                                                  | Use it to                                           |
| --------------------------------------------------------- | --------------------------------------------------- |
| [Query symbols](/api-reference/query-symbols)             | Find declarations and compose semantic query steps. |
| [Source read](/api-reference/source-read)                 | Read bounded source for an admitted selector.       |
| [Check diagnostics](/api-reference/check-diagnostics)     | Inspect IDEA diagnostics for a path.                |
| [Add declaration](/api-reference/add_declaration)         | Apply one exact-target declaration change.          |
| [Workspace lifecycle](/api-reference/workspace-lifecycle) | Explicitly control a hosted IDEA project.           |

## Detailed schemas

Expand **Callable schemas** in the sidebar for the hosted tool inputs and
responses. Expand **Transport results** or **Semantic results** for their
component schemas. The `POST /callables/...` labels organize documentation;
Kast does not expose them as HTTP endpoints. These generated pages preserve
the complete installed contract, including less common outcome variants.