feat: add cluster filter to list_alert_rules MCP tool (#4288)

[AvijitBhattacharjee]

Title: feat(mcp): add cluster and cluster_match filter to list_alert_rules

Closes #4288
Summary
Adds optional cluster and cluster_match parameters to the list_alert_rules MCP tool, allowing users to scope results to a specific cluster instead of always returning every rule from alert_rules.yml and ems_alert_rules.yml.
Changes
mcp/pkg/mcptypes/types.go

Added ListAlertRulesRequest struct with cluster (exact match) and cluster_match (regex) fields, consistent with GetActiveAlertsRequest and InfrastructureHealthRequest.

mcp/cmd/server/main.go

Updated ListAlertRules handler signature from struct{} to mcptypes.ListAlertRulesRequest
Added input validation (rejects " and \ in cluster values) matching the pattern used by GetActiveAlerts and InfrastructureHealth
Added filterRulesByCluster — filters []rules.RuleInfo by checking the rule's expr (substring match) and labels["cluster"] (exact or regex match)
Added ruleMatchesCluster — core matching logic handling exact cluster name and compiled regex cases
Added filter annotation in response output when filtering is active
Updated Total Rules count to reflect filtered results

mcp/cmd/descriptions/descriptions.go

Added ListAlertRulesDesc constant with full documentation of the new parameters, replacing the previous inline string in createMCPServer()

[cla-bot]

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[cla-bot]

Thank you for your interest in contributing to the Harvest project! We require contributors to sign our Corporate contributor license agreement (CCLA), and we don"t have the user(s) @AvijitBhattacharjee on file. In order for us to review and merge your code, please follow the instructions in step 6 of creating a pull request.
After signing the CCLA, you can ask us to recheck this PR by posting @cla-bot check as a comment to the PR.

[rahulguptajss]

@AvijitBhattacharjee Thanks for the contribution. Could you refill the CCLA form as your username in the filled form has a space as Avijit Bhattacharjee. It should be AvijitBhattacharjee. Once you do that, we can review the PR. Thanks.

[AvijitBhattacharjee]

AvijitBhattacharjee

@rahulguptajss I have resubmitted the form with AvijitBhattacharjee. Kindly check and please proceed for this PR. Thanks.

[rahulguptajss]

AvijitBhattacharjee

@rahulguptajss I have resubmitted the form with AvijitBhattacharjee. Kindly check and please proceed for this PR. Thanks.

Thanks @AvijitBhattacharjee . It looks good now.

[Hardikl]

Verified this local branch changes,

Prompt: show me all firing alert rules
Result: which is exactly same as what prometheus alerts are showing.

Status of the firing alerts in prometheus based on cluster

Prompt: ok, can you show all firing alerts instance of certificate expired of cluster name a250
Result: shows 17 records, which uses cluster match regex

Prompt: great, can you show all firing alert instance of certificate expired of cluster name as sa-tme-flexpod-a800-rdma
Result: shows 10 records, which used cluster filter

[AvijitBhattacharjee]

Thanks @Hardikl for the approval. Please let me know how many approval needed to merge and who can merge the PR? I think I will not have the merge access.

[Hardikl]

There is slight change, Prior was tested with firing alert which are not in scope of this PR.

Now, I have validated those static rules with these changes in alert_rules.yaml, PR chances seems good. Updating the screenshot of the same.

[AvijitBhattacharjee]

@rahulguptajss @Hardikl now I have modified the PR title and the check passed. @Hardikl Thanks for the approval.

It seems there are few workflows requires approval from a maintainer. Kindly check.

[cgrinds]

Thanks for the contribution @AvijitBhattacharjee We've merged your changes, and they are available in the latest nightly build.

[AvijitBhattacharjee]

Hi Sir, I am really glad to make my first open source contribution in NetApp. I am really grateful to the reviewers for merging my changes. I would like to contribute more. Thanks again. Regards, Avijit Bhattacharjee https://www.linkedin.com/in/avijit-bhattacharjee--/

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On Mon, Jun 1, 2026 at 11:56 PM Chris Grindstaff ***@***.***> wrote: *cgrinds* left a comment (NetApp/harvest#4302) <#4302 (comment)> Thanks for the contribution @AvijitBhattacharjee <https://github.com/AvijitBhattacharjee> We've merged your changes, and they are available in the latest nightly build <https://github.com/NetApp/harvest/releases/tag/nightly>. — Reply to this email directly, view it on GitHub <#4302?email_source=notifications&email_token=ALWS3UPP6H5F7NCQQJDFSQT45XDHFA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTINJZGUZTMMJSHA4KM4TFMFZW63VHNVSW45DJN5XKKZLWMVXHJLDGN5XXIZLSL5RWY2LDNM#issuecomment-4595361288>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ALWS3UOPMH6XW635LXSMKML45XDHFAVCNFSM6AAAAACZKB44HKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DKOJVGM3DCMRYHA> . You are receiving this because you were mentioned.Message ID: ***@***.***>