`-O` / `--tools` can already narrow the exposed tool set, but it needs every tool spelled out by name. `-S` / `--scope` (`GITEA_SCOPES`) complements it by selecting whole scopes, using the same names the `Scope` column of the tool tables documents.
```bash
gitea-mcp -S issue,pull_request # only those scopes
gitea-mcp --scope repository,branch --tools get_me # those scopes plus one extra tool
```
## What changed
- Each scope is one `tool.Tool` registry carrying a canonical name, so `operation/repo` is split into the six scopes its files already imply: `repository` (`repo.go` + `tree.go`), `file`, `branch`, `tag`, `commit`, `release`. The other twelve packages map 1:1, giving 18 scopes.
- The two allowlists combine as a **union**: with neither set every tool loads; with only `--tools` set behaviour is unchanged; with both set, the selected scopes' tools plus the individually named tools load. `-r` / `GITEA_READONLY` still hides write tools on top.
- Scope names are normalized on input (case, spaces, hyphens), so `Pull Request`, `pull-request` and `PULL_REQUEST` all resolve to `pull_request`. Unknown names only warn and list the valid scopes, mirroring how `--tools` treats unknown tool names.
- The `Scope` column of all three READMEs now uses the canonical names verbatim, so it doubles as the reference for `--scope`, and `TestReadmeToolTables` compares that column against the registry in both directions — no translation table needed.
- Flag parsing moves from `cmd.init()` into `Execute()`. `main()` only ever calls `Execute()`, so this is behaviourally equivalent, and it makes the `cmd` package testable at all: previously the `init()` parse of `os.Args` hit `flag.CommandLine`'s `ExitOnError` on `go test`'s own `-test.*` flags.
## Verification
`make fmt`, `make lint-go` (0 issues) and `go test ./...` all pass. New tests cover the filter matrix (no filters / scope-only / tools-only regression / union / read-only interaction / unknown scope), scope-name uniqueness across `domainTools`, and the flag+env parsing and normalization.
Smoke-tested `tools/list` over stdio against the built binary:
| flags | tools exposed |
| :-- | :-- |
| _none_ | 54 (identical to `main`) |
| `-S branch` | `create_branch`, `delete_branch`, `list_branches` |
| `--scope 'Pull Request,TAG'` | the 4 `pull_request` + 4 `tag` tools |
| `-O get_me` | `get_me` (unchanged) |
| `-S commit -O get_me` | `get_commit`, `list_commits`, `get_me` |
| `-S file -r` | `get_dir_contents`, `get_file_contents` |
| `-S bogus,issue` | the 4 `issue` tools, plus a warning naming the valid scopes |
Reviewed-on: https://gitea.com/gitea/gitea-mcp/pulls/219
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: yp05327 <576951401@qq.com>
yp05327