cgis_analyze_impact
Trace upstream callers, importers, subclasses, and type references to reveal what breaks if you change a symbol. Configure depth and output as Mermaid diagram or JSON.
Instructions
Upstream subgraph of one FQN: everything that reaches it within depth hops.
Follows every edge except containment — in practice callers, importers,
subclasses, type references and DI dependents — within internal code, so this
answers "what breaks if I change X?". The
enclosing class or file and stdlib/third-party nodes are left out unless
``include_structure`` / ``include_external`` ask for them — the same view as
the CLI's ``impact``. For what X depends on use
``cgis_trace_flow``; for only the members of a module or class,
``cgis_get_structure``; for a source-included brief to read before editing
one symbol, ``cgis_context``.
``output_format="mermaid"`` (default)
returns a diagram; ``"json"`` returns a joinable ``{root, nodes, edges,
coverage}`` payload with real FQNs — letting an agent compute set
differences (e.g. "which route handlers never reach ``verify_ownership``?")
directly. ``coverage`` counts unresolved calls whose name matches a
traversed function, method or class: callers that may be missing, named in
``top_unresolved``. It is an upper bound — a common name matches calls on
unrelated objects, which the names make visible.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| fqn | Yes | Fully qualified name, e.g. pkg.module.Class.method. A unique dot-boundary suffix also resolves; an ambiguous one returns candidates. Use cgis_find_symbol to look a name up. | |
| depth | No | Maximum edge hops upstream, over callers, importers, subclasses, type references and DI dependents (plus the enclosing class or file with include_structure). | |
| db_path | No | SQLite graph built by cgis_ingest. A relative path resolves against the MCP server's working directory, not the agent's — prefer an absolute path. | graph.db |
| output_format | No | "mermaid" for a diagram, or "json" for a payload with real FQNs (case-insensitive). Any other value returns an error. | mermaid |
| include_external | No | Also return stdlib, third-party and unresolved call targets — calls on values whose type is decided at runtime. Off by default, as in the CLI, because they dominate the payload; in json, coverage/top_unresolved still counts what was dropped. | |
| include_structure | No | Also follow containment (CONTAINS/DECLARES): a module's or class's own members, and the class or file enclosing a symbol. Off by default, as in the CLI; cgis_get_structure is the tool for members alone. |
Output Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |