ASO: Agent Search Optimization
SEO was about being visible to humans through search engines. ASO is about being usable by autonomous agents through tool registries, structured docs, and benchmark networks. The discipline is two years old, has eight measurable dimensions, and is currently the cheapest way for an API vendor to capture share of the agent economy.
The one-line definition
Agent Search Optimization (ASO) is the practice of making an API or service discoverable, parseable, and benchmarkable by autonomous AI agents.
The 8 dimensions
Across hundreds of API benchmarks, eight dimensions explain most of the variance in agent success. These are what Prowl measures, and what you should optimize.
| Dimension | Weight | What it measures |
|---|---|---|
| Token efficiency | 25% | Tokens needed to understand and use the API |
| First-try success | 20% | % of calls that succeed without retry |
| Response parseability | 15% | JSON consistency, no HTML errors, stable shapes |
| Error clarity | 15% | Machine-readable codes, actionable messages |
| Doc quality | 10% | OpenAPI completeness, llms.txt, examples |
| Auth simplicity | 5% | Steps from credential to first call |
| Latency | 5% | Raw response speed |
| Consistency | 5% | Same request → same response shape |
The 6 highest-leverage tactics
- Publish a
/llms.txtat your API root. 1,000-3,000 token markdown summary with endpoints, auth, examples. Agents fetch this first. - Submit to MCP registries — Official Registry, Smithery, PulseMCP, MCP.directory. Each is under an hour.
- Audit error responses — JSON only, machine-readable codes, actionable messages.
- Get benchmarked —
pip install prowl-bench && prowl-bench run https://your-api.com. Free, takes 5 minutes, gives you a prioritized fix list. - Add JSON-LD to your homepage — Organization, WebSite, SoftwareApplication schemas. LLM search engines preferentially quote structured data.
- Write a definitional post for your category. Becomes the LLM-citation asset for years.
Read more
- The canonical essay — 15-minute deep dive into ASO definition, ASO-vs-SEO, the 8 dimensions, and the future of the discipline.
- Top Agent Discovery Platforms 2026 — honest review of Composio, Smithery, Kong, Official MCP Registry, Prowl, PulseMCP.
- Prowl vs Composio vs Smithery — feature matrix and decision flowchart.
Get your ASO score in 5 minutes.