Cloudflare AI Search vs Vespa

Cloudflare AI Search

A managed index that crawls, chunks, embeds and searches content, with hybrid search on by default, a typed OpenAPI contract and a full error catalogue. Generally available since 1 October 2026, with billing from 1 November. Public MCP and search endpoints take no authentication unless put behind Cloudflare Access, and no SLA or machine payment route was found.

Vespa

Vespa Cloud publishes hourly unit prices, a 99.5% uptime agreement for paying customers and a trial with $300 of credits and no card. Every call needs an application package deployed first, no OpenAPI file was found in the reviewed documentation, and Vespa.ai says it has no official public MCP server.

Cloudflare AI Search

1. Use /ai-search/namespaces/default/instances/{id}/search. The un-namespaced and /autorag/rags/ paths are deprecated
2. Set ai_search_options.retrieval.max_num_results (1 to 50, default 10) and match_threshold (default 0.4) to bound the context you read
3. On 429 code 7069 the monthly query quota is spent. Wait or upgrade rather than retry
4. Expect up to six hours before website or R2 changes are searchable. Trigger a sync job, at most once every 30 seconds, after you write
5. Filters match only the first 64 bytes of a string. Use a $gte/$lt range on folder to match a folder and its subfolders

Vespa

1. Deploy an application package with a schema before feeding or querying. Use vespa deploy and wait for the endpoint to report ready
2. Send a token as Authorization: Bearer only to the endpoint marked Token. The mTLS endpoint needs the client certificate and key
3. Set hits, offset and presentation.summary on queries. hits is capped at 400 by default and the query timeout defaults to 0.5s
4. On 429 from /document/v1 reduce the feed rate and back off. On 507 stop feeding, because the cluster is out of memory or disk
5. Use the condition parameter for test-and-set writes and expect 412 when it fails or the document is missing