Enrich-Retrieve-Rank: Scaling Capability Discovery Beyond In-Context Routing

2026-08-24Computation and Language

Computation and LanguageArtificial IntelligenceInformation Retrieval
AI summary

The authors address a problem where systems with thousands of components called MATS (Models, Agents, Tools, Skills) struggle to find the right one quickly using current methods. They propose a two-step approach: first, enrich the component data offline to create better searchable profiles, then use an online method to retrieve and rank candidates without testing each one. Their method works much better than existing in-context routing approaches, especially as the number of components grows, and is more cost-effective. This new pipeline is already used in a large multi-agent platform.

MATSagent ecosystemscapability discoveryin-context routingretrievalrankingmetadata enrichmentlarge language modelsmulti-agent systemssearch pipelines
Authors
Nazib Sorathiya, Daniel Zhang, Bardiya Akhbari
Abstract
Agent ecosystems now include thousands of MATS components (Models, Agents, Tools, and Skills), yet their discovery still relies on in-context routing. These systems read a registry (names, hints, or descriptions, as context budget permits), pick a candidate, invoke it, and retry on failure. This pattern degrades with scale, and registries are growing fast. We recast capability discovery as search over a registry by defining an offline enrichment step that turns sparse metadata into searchable profiles, and an online retrieve-then-rank pipeline that returns a ranked shortlist without invoking any candidates online. We show that from N=10 to 7,278 capabilities, in-context routing's top-1 accuracy (Match@1) collapses (0.85 to 0.12), while retrieve-then-rank degrades more gently (0.81 to 0.39) because its reranker still ranks the right capability first 0.70-0.87 of the time once retrieval finds it. In the Nova Micro sweep, the crossover is around N=500. We compare against two in-context baselines. Full-Ctx puts the whole registry in the prompt and asks the LLM to pick. Search&Pick gives the LLM a search tool to narrow candidates before it picks. At full scale the pipeline leads Search&Pick by 6.5 percentage points (pp) on Match@1 at about half the cost. It reduces cost 70x versus Full-Ctx. We use a fixed configuration (same enrichment, retriever, and scorer weights) across agent, tool, and skill registries. The pipeline runs in production as the default capability-discovery layer of a large-scale multi-agent platform.