MCP for an assistant, an API for your application
MCP exposes search as a tool the assistant can call. A direct API integration is a server function your application owns. They can use the same underlying retrieval service without having the same authentication, limits or tool behavior.
For a personal coding workflow, a hosted MCP connection can avoid writing a wrapper. For a customer-facing product, an authenticated server-side API handler gives you control over quotas, caching, response validation and which credentials can be used.
Do not confuse a provider's documentation MCP with its web-search MCP. Searching that provider's docs is not evidence that an agent can retrieve the public web.
Official web-search MCP options
| Provider | Documented connection | Check before using |
|---|---|---|
| Exa | Hosted MCP; no key needed to begin | Tool set and free-use limits versus direct API access |
| Parallel | https://mcp.parallel.ai/mcp | Lower-limit search/fetch without a key; research requires authentication |
| Perplexity | Remote API MCP and a local option | Sign-in/key path and which tool produces raw sources versus an answer |
| Tavily | Hosted MCP with OAuth/client setup | Selected tools, account allowance and search depth |
| Context.dev | https://mcp.context.dev/mcp with OAuth | Search versus scrape, Answers and specialist data tools |
| Brave | Official MCP implementation | Subscription credential and Web versus LLM Context tools |
Availability is documented, not a compatibility score. Client versions, administrator policy and tool permissions can still prevent a connection from working. Follow the linked official client instructions rather than copying a stale token-bearing URL from a tutorial.
A keyless starting point in Codex or Claude Code
Parallel documents these hosted-MCP commands. They are examples for a client you control, not commands we have executed on your behalf. They do not establish a free production quota for an application.
codex mcp add parallel --url https://mcp.parallel.ai/mcpclaude mcp add --transport http parallel https://mcp.parallel.ai/mcpStart a fresh conversation if the client requires it, inspect the tool list and choose a public lookup. If sign-in or a broader permission prompt appears, review it before authorizing. Keep provider keys in supported secret storage, not in a shared chat or screenshot.
Prove the intended tool actually ran
An assistant can answer from memory or invoke its built-in search instead of your newly added MCP tool. A plausible answer is not proof of a working integration.
- Ask for a current fact from an identifiable official source.
- Inspect the tool trace and confirm the intended provider/tool was invoked.
- Keep the exact query, source URLs, response status and client version.
- Check a failure or no-result case. The assistant should not turn a tool error into a confident factual answer.
- Repeat with a task from your real workflow, keeping secrets out of the public record.
Use retrieval benchmarks to select candidates, not to claim a client integration has passed. Our August API run did not test all the MCP paths on this page.
Keep the agent's access and usage bounded
Limit tool scope and calls per task. Treat snippets and pages as untrusted evidence, not as instructions to run commands or disclose data. A search MCP should not silently gain authority over files, accounts or payments because an external page asks it to.
Check whether the client sends private conversation context to the search provider. Prefer a narrowly phrased query over an entire internal transcript. Then inspect the evaluation allowance and paid usage model before scaling the workflow.
Sources and review dates
Documentation review: October 27, 2026. Our own measured retrieval runs: August 23, 2026. External reports retain their publisher and measurement window.
Corrections: email faizank@docsalot.dev with an official source.