Linkup vs Tavily API + MCP

Linkup

Per-call prices from $0.005, and no credit taken for errors, missing parameters or empty results. 429 covers both exhausted credit and rate limiting, with no Retry-After.

Tavily API + MCP

Keyless search and extract, plus a free 1,000 credits a month with no card. x402 covers advanced search only, not extract, map, crawl or research.

Linkup

1. On 429, check the credit balance before backing off. The same code means out of credit
2. Pass reasoningDepth: "S" to research unless you need more. The MCP default is L at $1.50
3. Start with depth=fast and outputType=searchResults. Deep costs $0.05, ten times as much
4. Send the key as an Authorization: Bearer header, not ?apiKey= or a command-line argument
5. Poll linkup-get-research with the task id. Research runs take minutes

Tavily API + MCP

1. Try X-Tavily-Access-Mode: keyless first for search and extract, then switch to a key or x402 when the limit hits
2. Send the key in Authorization: Bearer, not ?tavilyApiKey= in the MCP URL
3. On 429, wait for Retry-After. A 432 or 433 means a spend limit, and retrying won't help
4. Run /map before /crawl to bound the crawl, since crawl is billed as map plus extract
5. Research is async and runs 4 to 250 credits. Create the task, then poll /research/{request_id}