CLI client changeddocs/draft/tools/inspector/cli
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Upstream edited this page at 2 Aug 2026 23:45 UTC, give or take a minute or two: the time comes from Anthropic’s own sitemap rather than from a commit. This site recorded the change at 28 Sep 2026 22:07 UTC.
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4242
4343## Methods
4444
45| `--method` | Required companions | Notes |
46| ------------------------------ | ----------------------------------------------------- | -------------------------------------------------------------------------------- |
47| `initialize` | None | Connect-only probe: `{serverInfo, protocolVersion, capabilities, instructions}`. |
48| `tools/list` | None | |
49| `tools/call` | `--tool-name`, plus `--tool-arg` / `--tool-args-json` | |
50| `resources/list` | None | |
51| `resources/read` | `--uri` | |
52| `resources/templates/list` | None | |
53| `prompts/list` | None | |
54| `prompts/get` | `--prompt-name`, `--prompt-args` | |
55| `logging/setLevel` | `--log-level` | Legacy era only; modern servers opt in per request instead. |
56| `servers/list`, `servers/show` | None | Read the catalog **without connecting** to anything. |
45| `--method` | Required companions | Notes |
46| - | - | - |
47| `initialize` | None | Connect-only probe: `{serverInfo, protocolVersion, capabilities, instructions}`. |
48| `tools/list` | None | |
49| `tools/call` | `--tool-name`, plus `--tool-arg` / `--tool-args-json` | |
50| `resources/list` | None | |
51| `resources/read` | `--uri` | |
52| `resources/templates/list` | None | |
53| `prompts/list` | None | |
54| `prompts/get` | `--prompt-name`, `--prompt-args` | |
55| `logging/setLevel` | `--log-level` | Legacy era only; modern servers opt in per request instead. |
56| `servers/list`, `servers/show` | None | Read the catalog **without connecting** to anything. |
5757
5858Stream- or session-only methods (`logging/tail`, for example) are rejected, since a process that exits can't hold a stream open.
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106106
107107Every non-zero exit maps to a stable failure class, so a caller can branch on *why* without scraping prose:
108108
109| Code | Meaning |
110| ---- | ---------------------------------------------------------------------------- |
111| `0` | Success. |
112| `1` | Usage or unexpected error (the catch-all). |
113| `2` | No MCP App found on the tool (`--app-info` probe). |
114| `3` | Server requires authentication (401/403, `WWW-Authenticate`, OAuth). |
115| `4` | Server unreachable (DNS, connection refused, timeout, `fetch failed`). |
116| `5` | Tool error: `tools/call` returned `isError: true`, or the tool wasn't found. |
109| Code | Meaning |
110| - | - |
111| `0` | Success. |
112| `1` | Usage or unexpected error (the catch-all). |
113| `2` | No MCP App found on the tool (`--app-info` probe). |
114| `3` | Server requires authentication (401/403, `WWW-Authenticate`, OAuth). |
115| `4` | Server unreachable (DNS, connection refused, timeout, `fetch failed`). |
116| `5` | Tool error: `tools/call` returned `isError: true`, or the tool wasn't found. |
117117
118118On any non-zero exit the CLI also writes a **single JSON line to stderr**:
119119
No line in this hunk matches that.