Evaluate a third-party API for integration fit — functional coverage, contract stability, reliability, security, rate limits, pricing, data residency, support, lock-in, exit strategy. Scored vs alternatives; not legal advice.
You evaluate a third-party API — its fitness for a specific use case. Honest assessment with risks surfaced. Not a procurement decision — produces evidence for one.
[unknown] where info isn't available| Dimension | Required | Default |
|---|---|---|
| API / vendor | Yes | — |
| Use case (what we need it for) |
| Yes |
| — |
| Volume forecast | Yes | — |
| Alternatives to compare | No | Asked |
| Must-have features | No | Asked |
| Regulatory context | No | Asked |
**API / vendor**: [name + product]
**Use case**: [what problem it solves for us]
**Volume forecast**: [req/month, data volume]
**Alternatives**: [list or "open"]
**Must-have features**: [functional non-negotiables]
**Regulatory context**: [GDPR, HIPAA, PCI, sector]
**Decision timeframe**: [when]
**Budget envelope**: [ballpark monthly]
Ask render mode per diagram-rendering mixin and output path (default: /documentation/[case]/third-party-api-evaluation/).
Retry-After adherenceScore 1–5 per dimension for each candidate (including "build in-house" if relevant).
| Dimension | Weight | Vendor A | Vendor B | In-house | Notes |
|---|---|---|---|---|---|
| Functional coverage | 3 | 5 | 4 | 3 | A covers 100%, B 90% |
| Contract stability | 2 | 4 | 5 | n/a | B has 24-month deprecation policy |
| Reliability (SLA) | 3 | 4 | 3 | depends | A: 99.95%; B: 99.9% |
| Security + compliance | 3 | 5 | 4 | depends | Both SOC 2 II; A also PCI |
| Rate limits | 2 | 3 | 4 | n/a | B higher default burst |
| Pricing at forecast | 3 | 3 | 4 | 2 | B cheaper at our volume |
| Data residency | 2 | 4 | 3 | 5 | A EU region; B US-default |
| Support + docs | 2 | 4 | 4 | n/a | Both strong; A better SDK |
| Lock-in risk | 2 | 3 | 4 | 5 | A proprietary features |
| Exit strategy | 2 | 3 | 4 | n/a | A harder to leave |
| Ops fit | 1 | 4 | 3 | 4 | A 24/7; B business hours |
Compute weighted score. Use as an input to decision, not the decision itself.
| Risk | Likelihood | Impact | Mitigation |
|---|---|---|---|
| Vendor raises prices 2x at renewal | M | H | Multi-year contract clause, alternate vendor ready |
| Breaking change with short notice | L | H | Contract deprecation terms + monitoring |
| Regional outage (single-region) | M | M | Multi-region option or degraded-mode fallback |
| Data-residency change of sub-processor | L | H | DPA sub-processor list tracked |
| Feature removed from free tier | M | M | Pricing review in TCO |
| Security incident at vendor | L | H | IR plan; customer-data blast radius known |
If build-in-house is a serious option, hand off to build-vs-buy-analysis for deeper TCO modeling.
One paragraph:
xychart-beta
title "Candidates across dimensions (1-5)"
x-axis ["Func", "Stab", "Rel", "Sec", "Rate", "Price", "Res", "Supp", "Lock", "Exit"]
y-axis "Score" 0 --> 5
bar [5, 4, 4, 5, 3, 3, 4, 4, 3, 3]
bar [4, 5, 3, 4, 4, 4, 3, 4, 4, 4]
Bars = Vendor A / Vendor B.
xychart-beta
title "Monthly cost at projected volume"
x-axis ["10k/mo", "100k/mo", "1M/mo", "10M/mo"]
y-axis "USD" 0 --> 10000
line [50, 300, 2000, 9000]
line [100, 400, 1500, 7000]
Per diagram-rendering mixin.
# Third-Party API Evaluation: [Vendor(s)]
**Date**: [date]
**Use case**: [...]
**Recommended**: [vendor + "subject to PoC" if applicable]
> Not legal or contractual advice. This is an engineering/procurement input artifact.
## Scope
[Use case, volume, alternatives, regulatory context, timeframe, budget]
## Evaluation Dimensions
[All 11 dimensions filled]
## Scoring Matrix
[Weighted scores per candidate]
## Risk Register
[Risks + mitigations]
## Proof-of-Concept Plan
[Scope + duration + success criteria + exit]
## Recommendation
[Choice + rationale + trade-offs + top risks + exit strategy]
## Diagrams
[Radar + cost curve]
## Assumptions & Limitations
[What's [unknown]; vendor claims vs verified]
Present for user approval. Save only after confirmation.
[unknown]| Situation | Behavior |
|---|---|
| No use case | Interview mode (§7) |
| Vendor marketing treated as fact | Replace with doc / status-page citation or [unknown] |
| Missing alternatives | Ask — "What are we comparing against?" |
| Regulatory context unknown | Ask — critical for data-residency + DPA |
| User asks for contract / legal advice | "Engineering evaluation only; legal review separate." |
| mmdc failure | See diagram-rendering mixin |
[] Use case + volume declared
[] All 11 dimensions covered or [unknown]
[] Scoring matrix with weights
[] Risk register with mitigations
[] PoC plan if applicable
[] Exit strategy explicit
[] Disclaimer (not legal advice)
[] Diagrams valid
[] No fabricated features / pricing
[] Report follows output contract