gerritcodereview find-dependencies
Find and interpret the full dependency picture for one or more Gerrit changes.
The tools get_depends_on and get_dependents are provided by the
gerrit_mcp_server_depends_on extension. They are available whenever
gerrit-mcp-server is running with the depends-on extension installed and a
configured Gerrit host that has the depends-on plugin enabled.
Dependency types
| Type | Source | Tool |
|---|---|---|
| Depends-on | Explicit Depends-on: annotation in the change message, parsed by the depends-on plugin |
get_depends_on |
| Git-chain parent | Implicit: this change's commit has a parent commit that is also an open Gerrit change | get_git_parent_changes |
A dependency can be resolved (mapped to a numeric change ID) or
unresolved (only has an I... change key ("Change-Id") that couldn't be
matched to a change in the configured deliverables).
Quick reference
| Goal | What to do |
|---|---|
| What does change X depend on? | get_depends_on(X) + get_git_parent_changes(X) in parallel |
| Which changes depend on X? | get_dependents(X) |
| Are all dependencies merged? | Get deps, then get_change_details on each; check status |
| Full dependency chain | Recurse: get deps, then get deps-of-deps (track visited IDs) |
| Set of changes | Call both tools for each change ID in parallel, deduplicate |
Workflow: single change
- Call
get_depends_on(change_id)andget_git_parent_changes(change_id)in parallel. - Merge the results:
- From
get_depends_on: each entry withresolved: truehas achange_number; unresolved entries have a Change-Id inunresolved. - From
get_git_parent_changes: each entry is an open parent change (or null if the parent commit is not a tracked Gerrit change, e.g. a merged branch tip).
- From
- For each resolved dependency, optionally call
get_change_detailsto show its status (open / merged / abandoned) and subject. - Present as a structured list grouping Depends-on and git-chain deps separately.
Workflow: set of changes
Call both tools for every change ID. Use parallel tool calls to avoid sequential latency. Deduplicate by change number (the same upstream change may appear as a git-chain parent of multiple changes in the set).
Recursive traversal
To build a full dependency chain:
- Start with the target change(s).
- Maintain a visited set of change numbers.
- For each unvisited dependency, call
get_depends_onandget_git_parent_changes. - Add newly discovered deps to the queue; add the current change to visited.
- Stop when: the queue is empty, all deps are merged/abandoned, or a configurable depth limit is reached (default: 5 levels).
- Detect cycles: if a change appears as its own (transitive) dependency, flag it rather than looping.
Interpreting unresolved deps
An unresolved entry means the plugin found a Depends-on: I... annotation but
could not match that Change-Id to any change in the configured deliverables
(project/branch pairs). This happens when:
- The depended-on change is on a different project or branch not in the plugin's deliverables config.
- The change was abandoned or deleted.
- The Change-Id (I) is a typo.
Surface unresolved deps as-is with the raw key and note that the status cannot be determined without manual lookup.
Finding what depends on a change (reverse lookup)
Use get_dependents(change_id) to find changes that have declared
Depends-on: <change_id>. This uses the independson:<change_id> query
operator.
Troubleshooting
| Symptom | Fix |
|---|---|
get_depends_on returns empty depends_ons |
The change has no Depends-on: annotation, or the last Depends-on: line is blank (which clears all deps). |
get_git_parent_changes returns empty list |
The change's parent commit is not an open Gerrit change (e.g. it's the branch tip or already merged). This is normal for standalone changes. |
| Unresolved deps for known changes | The depended-on change may be on a project/branch not in the plugin's deliverables. Try looking up the Change-Id directly with query_changes(change:<Change-Id>). |