Should my agent depend on the MCP server com.rubrkit/rubrkit?

Verdict: allow — rich-solo — safe to depend on As of 2026-08-15T11:28:18Z: a dated observation with receipts, not a warranty.

rubrkit

com.rubrkit/rubrkit

MCP-native AI evaluation: rubric audits, eval suites, and proof reports for AI/LLM output.

— the operator's own registry description reported

Publisher com.rubrkit · first seen 2026-08-12 · endpoint https://www.rubrkit.com/api/v1/mcp

allow

verdict

rich-solo

cluster

ok_tools

answers

tools served

Dependency rating derived

allow — rich-solo — safe to depend on

Cluster rich-solo · distinctiveness 0.633 (unusual). Every figure is a percentile or class within the 11,094-server census — see the whole spectrum.

Reach — can an agent get to it?

answersalive_tools

latency117 ms

vs populationtypical

protocolcurrent

authopen

Use — can it use it?

tools41

vs populationhigh

capabilities3

harnessB

Trust — can it rely on it?

identitysolo

servers on its host1

verifiabilityunassessed

duplicate inventoryno

drift events0

answers trueno primary

🔏 Signed receipt rr_185a1f70bf0077484bc44071 · ed25519 · key rs-rcpt-2026-08 — this rating is tamper-evident; an agent gets the full signature from check_server and can verify it against the published key.

Tools last seen

rubrkit_add_golden_case rubrkit_apply_audit_rewrite rubrkit_convert_to_rubr_flow rubrkit_create_artifact_bundle rubrkit_create_drift_monitor rubrkit_delete_artifact_bundle rubrkit_export_proof_report rubrkit_hard_delete_artifact_bundle rubrkit_list_artifact_bundle_versions rubrkit_list_artifact_bundles rubrkit_list_artifact_files rubrkit_list_audits rubrkit_list_drift_monitors rubrkit_list_evals rubrkit_list_file_versions rubrkit_list_golden_cases rubrkit_list_job_events rubrkit_list_rubr_flow_conversions rubrkit_poll_job rubrkit_read_api_doc rubrkit_read_artifact_bundle rubrkit_read_artifact_file rubrkit_read_audit rubrkit_read_drift_observations rubrkit_read_eval rubrkit_read_input_drift rubrkit_read_openapi_contract rubrkit_read_proof_report rubrkit_read_rubr_flow_conversion rubrkit_read_validity_drift rubrkit_record_outcome rubrkit_restore_artifact_bundle_version rubrkit_restore_file_version rubrkit_retire_golden_case rubrkit_run_drift_check rubrkit_run_evals rubrkit_search_api_docs rubrkit_set_drift_monitor_status rubrkit_start_audit rubrkit_update_artifact_file rubrkit_upload_artifact_files

Harness readiness observed

Can an agent's harness pick this tool and call it correctly? Graded on the three things an agent reads — name, description, typed parameters. Band B — usable, with rough edges.

legibility check	tools passing	ok
name is clear & specific	41/41	✓
has a description	41/41	✓
description is substantive	41/41	✓
parameters are typed	41/41	✓
parameters are described	1/41	1/41

41 of 41 tools graded · 41 with a captured input schema. RS-008, Tier-1 — no domain knowledge, applies to any tool. “Alive” is not the same as “usable”.

Truth checks observed

Not in the Tier-2 trade lane, or not yet checked. Tier-2 re-derives a server's answers against published primary sources — see truth checks.

Protocol conformance observed

2025-06-18

protocol version

—

session model

0.1.0

server version rubrkit

Capabilities: prompts resources tools

Drift

No confirmed drift on record. Baseline set 2026-08-14; changes appear here after human review.

History observed

Every probe we made, oldest → newest (2 shown, 2026-08-12 → 2026-08-14). Green answered · amber answered-but-walled · red no useful answer. A gap in our cadence is a gap in coverage, not evidence about the server.

changelog (1 events)

date	type	what changed
2026-08-12	outcome	first probe: ok_tools

raw probe records

probed (UTC)	outcome	http	ms	protocol
2026-08-14T19:58:27Z	ok_tools	200	117	2025-06-18
2026-08-12T05:33:42Z	ok_tools	200	168	2025-06-18

Watch or embed this verdict

Operators: put the live verdict in your README — it updates with every census, links back here, and is a dated observation, never a warranty:

[![Robin Saige verdict](https://robinsaige.com/badge/com.rubrkit/rubrkit.svg)](https://robinsaige.com/s/com.rubrkit/rubrkit)

Depend on it? Subscribe to its change feed — outcome changes and confirmed drift, no account needed. Building on it? The full dossier as JSON — verdict, rating, truth checks, history — stable enough to gate CI on.

← overview