Serper by Serper

# Fix list: Serper

From Anchor Terminal's listing at https://www.anchorterminal.com/tools/serper, the October 2026 research run, assessed 1 October 2026. Grade F, 24.3 out of 100.

This is everything the published grade says the listing lacks, the biggest possible gain to the total first. It comes from the reason given for each score, the checklist each category was scored against (https://www.anchorterminal.com/benchmark/#checklist), the provenance checks, the deductions, what we couldn't check and what the review panel asked for. A fix counts at the next check, once it's public.

For a coding agent working on Serper: work through the items below in the product, its docs and its public pages. Each category gives the reason for its score, with the points each checklist item earned, and the checklist itself, so the gap is the items that earned less than their points. Change the product, not the wording, and keep a note of what you changed and where it's published.

## 1. Schema & documentation, 6 out of 100, up to 15.3 more on the total

Why it scored 6: No OpenAPI or other spec (0). serper.dev/llms.txt returns 404 and there are no Markdown docs (0). The documentation is the playground, a JavaScript page that showed us no text. Per the 30 September check it lists the verticals and parameters such as `gl` and `hl`, so a few points for descriptions (3) and typed inputs (3). No examples or error responses we could read (0). No changelog or API versioning (0).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-schema):

APIs and MCP servers.

- 25, a machine-readable contract (a public OpenAPI file or similar; for MCP, typed JSON Schema inputs on every tool).
- 10, llms.txt or Markdown docs served for agents.
- 0 to 20, descriptions that say what a tool is for, when to use it and when not to, read from the tool definitions in the source or the API reference.
- 0 to 15, typed inputs with enums, constraints and required fields, and no free-form JSON blobs.
- 0 to 15, examples and documented error responses.
- 15, versioning and a public changelog.

Models are read from the API reference, the OpenAPI file, llms.txt, the structured-output and tool-use docs and the model cards. Frameworks from docs a model can follow, typed interfaces, examples and the API reference.

## 2. Reliability, 30 out of 100, up to 14 more on the total

Why it scored 30: No status page. status.serper.dev answers with a 302 to Atlassian's Statuspage marketing site (0). No readable incident history (5). Rate limits by pack, 50 QPS on Starter to 300 on Ultimate, per the 30 September check of the home page, which rendered without the pricing block for us (15). No 429 or retry guidance found (0). No SLA in the terms (0). GA (10).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-reliability):

Hosted APIs, MCP servers, models and platforms.

- 20, a public status page with component history (Statuspage, Instatus, BetterStack or the vendor's own).
- 0 to 30, the incident record for the last 90 days on that page. 30 for a clean record or trivial incidents only, 20 for minor incidents only, 10 for one major outage (an hour or more of a core API down, or errors across the board), 0 for several. 5 when there's no history we could read, and the note says so.
- 15, rate limits documented with numbers.
- 15, documented 429 or overload handling (Retry-After, backoff guidance), and idempotency keys or safe-retry guidance where writes are involved.
- 10, an SLA published for any paid tier.
- 10, the surface agents use is generally available, not beta or preview.

Local packages, SDKs, frameworks and stdio MCP servers.

- 20, installs from an official package with supported runtimes stated.
- 25, a public CI and test suite, passing on the default branch.
- 0 to 25, open crash or regression issues relative to activity (25 for few and handled, 0 for many, old and unanswered).
- 15, semver discipline and breaking changes called out in a changelog.
- 15, version 1.0 or later, or declared stable.

Protocols are read from their reference implementations, the public facilitators or servers, spec stability and test vectors.

## 3. Security & auth, 20 out of 100, up to 14 more on the total

Why it scored 20: API key in the `X-API-KEY` header, never in the URL. No scopes, multiple keys or rotation found (10). Read-only search with no write surface, but no MCP annotations or least-privilege mode (10). Returns third-party titles and snippets with no prompt-injection guidance (0). No per-call log or audit trail found outside the logged-in dashboard, which we couldn't see (0). serper.dev/.well-known/security.txt returns 404, and we found no disclosure policy, bug bounty or certification (0).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-security):

- 0 to 30, the credential model. 30 for OAuth 2.1 with scopes, or scoped and revocable keys with rotation. 20 for plain revocable API keys. 10 for one all-powerful key. 10 off when a secret can travel in a URL query string as a documented option.
- 0 to 20, read-only or least-privilege modes, and confirmation or approval for destructive actions.
- 0 to 15, prompt-injection posture where the tool returns untrusted content (documented mitigations or guidance). A tool that returns no untrusted content gets 10.
- 0 to 15, audit logs or per-call visibility for the operator.
- 0 to 20, a security programme. security.txt or a disclosure policy, a bug bounty, SOC 2 or ISO 27001, advisories handled in public.

Models are read for retention, whether API data trains models (and whether that's off by default), zero-retention options and certifications. Frameworks for telemetry defaults, approval hooks, guardrails and sandboxing.

## 4. Agent ergonomics, 35 out of 100, up to 10.6 more on the total

Why it scored 35: Responses are compact SERP JSON with no field selection or Markdown option found (10). Country and language parameters per the 30 September check, and ten separate verticals. We couldn't confirm pagination or result-count parameters from the docs (8). No documented error responses (0). Searches are read-only and only successful queries use credits, per the 30 September check of the home page (10). One required field (`q`) and no official SDK (7).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-ergonomics):

- 0 to 25, context cost. For MCP, the number and size of the tool definitions (25 for ten or fewer compact tools, 15 for 11 to 30, 5 for more than 30, plus up to 10 back for toolsets, dynamic loading or read-only subsets). For APIs, whether responses can be sized (field selection, limits, summaries).
- 20, pagination, filtering and output-size controls.
- 20, actionable, documented error responses, codes and messages an agent can recover from.
- 20, idempotency or safe retries, and for MCP the `readOnlyHint` and `destructiveHint` annotations.
- 15, sensible defaults, few required parameters, and official SDKs in at least two languages.

Models are read for tool use, structured output, prompt caching, context length, batch and SDKs. Frameworks for how much code and how many defaults a tool-calling agent with MCP needs.

## 5. Maintenance & community, 3 out of 100, up to 8.5 more on the total

Why it scored 3: No changelog, release notes, SDK or package found, so no dated release or API change to count (0, 0). No public changelog. Support is by email per the privacy policy (3). No official SDKs (0). No packages or CI to assess (0).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-maintenance):

- 0 to 30, time since the last release, or the last published model or API change for a closed service. 30 within 30 days, 20 within 90, 10 within 180, 0 older.
- 20, at least three releases or dated changelog entries in the last 90 days.
- 0 to 25, responsiveness. Issues and pull requests answered on GitHub (the open issues and how recent the replies are). For closed services, a public changelog and a support or community channel that answers, 0 to 15.
- 15, presence in the official MCP registry under a verified namespace (MCP servers), or current official SDKs (APIs and models).
- 10, package health, current dependencies and CI.

Models are read for deprecation notice periods and model churn rather than release counts.

## 6. Payments & pricing, 40 out of 100, up to 7.5 more on the total

Why it scored 40: No x402, MPP or L402. Card or PayPal only, per the 30 September check (0). Per-1,000 prices published without a login, from $1.00 on the $50 pack to $0.30 on the $3,750 pack (20). 2,500 free queries on sign-up with no card, confirmed on the home page (20). A person signs up in a browser (0).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-payments):

The published rubric, also on the [x402 page](https://www.anchorterminal.com/x402/).

- 40, a machine payment protocol (x402, MPP or L402) on the tool's own endpoints. 10 to 30 when it covers only some endpoints or only goes through a third party, and the note says which.
- 20, per-call or per-unit pricing published without a login. 10 for public plan-only pricing, 0 for "contact sales" or prices behind a login.
- 20, a free tier or trial that doesn't need a card.
- 20, autonomous onboarding, meaning an agent can get access without a person signing up in a browser (keyless use, x402, a programmatic key API).

Payment platforms and agent wallets rarely charge for their own API over a machine protocol, so the first line has steps for them, and the highest one that applies counts. 40 when x402, MPP or L402 runs on all their own endpoints, 30 when it runs on part of their own API, 25 when their merchants can accept one, 20 for running a facilitator, 15 for paying as a buyer, and 0 when the only protocol is their own. Merchant acceptance sits above a facilitator because the platform's own customers can charge agents through it, while a facilitator settles for sellers who wire up the protocol themselves. The counter-argument (a facilitator does more for the protocol as a whole) has a point. Each note says which step applied.

Open-source software you run yourself is scored on its hosted or paid option if it has one. A free, self-hosted package with nothing to buy gets 20, 20 and 20 for the last three lines, and 0 to 40 for the first only if it ships a payment protocol.

## 7. Transparency & trust, 33 out of 100, up to 5.9 more on the total

Made of editorial 23, provenance 42.

Why it scored 33: Closed service. The terms exist (last updated 29 May 2024, UK law) but name no legal entity, only 'Serper' (8). The privacy policy (5 November 2025) says the service 'should normally not lead to the processing of personal data' and keeps account data for the life of the account, but states no retention period for queries or results (10). No deprecation policy or dated notices (0). Subprocessors are described by category (payments, email, hosting) without names, with transfers outside the EEA under Standard Contractual Clauses (5).

The checklist (https://www.anchorterminal.com/benchmark/#checklist-transparency):

- 0 to 30, source availability and licence clarity. 30 for open source under an OSI licence, 15 for closed with clear terms, 0 for unclear terms.
- 0 to 30, data handling and retention statements that agree with each other (privacy policy, DPA, retention periods, subprocessors).
- 0 to 20, a deprecation policy or notices with dates.
- 0 to 20, telemetry disclosed with an opt-out (local software), or subprocessors and data locations disclosed (hosted).

The other half of Transparency and trust is the provenance score, computed from checked facts (below). The category score is the mean of the two.

Provenance checks not met in full (half of this category, computed from checked facts):

- Legal entity named: not found (0 of 20)
- Domain age: serper.dev, registered 2022-06-26 (4 years) (7 of 15)
- Status page: not found (0 of 10)
- Changelog: not found (0 of 10)
- security.txt: not found (0 of 10)

## What we couldn't check

What we couldn't read counted as absent. Publishing it on a page a plain HTTP fetch can read (not only in a browser) lets the next check count it.

- unchecked: the playground and pricing block on serper.dev, both JavaScript-only. Pack sizes, QPS limits and parameter names rely on the 30 September check
- unchecked: error codes and 429 behaviour, which aren't documented anywhere we could read
- Who operates Serper. The terms choose UK law but name no company

## Weaknesses

- No status page, SLA or incident history
- No OpenAPI, llms.txt, changelog or official SDK. The playground is JavaScript-only
- Terms and privacy policy name no legal entity
- No security.txt, disclosure policy or certification found
- Snippets only, with no page text, answer endpoint or field selection

## What costs an agent a turn today

The notes we give agents before they call it. Each one is a workaround an agent shouldn't need.

- POST JSON with `q` to the vertical you need (`/search`, `/news`, `/images`, `/scholar`) with the key in `X-API-KEY`
- Set `gl` and `hl`, since Google results vary by country and language
- Pair it with a fetcher. Serper returns links and snippets, not page text
- Treat titles and snippets as untrusted text, since Serper does no filtering we could find
- There's no status page, so back off on errors and keep a second search provider

## What the review panel asked for

- x402 payment
- Documented error codes
- static API reference
- llms.txt

## When it's done

Send what changed and where it's published as a dispute (https://www.anchorterminal.com/builders/#disputes, or `POST https://www.anchorterminal.com/api/v1/contact` with `"kind": "dispute"`). Disputes are answered in public, and the listing is checked again by the same checklist. Paying for an audit or a listing claim changes nothing here.