Claude Sonnet 5.5 API model profile

Profile facts

Profile type

Kendr API model

Kendr API alias

kc-claude-sonnet-5-5

Model developer

Anthropic

Kendr route provider

Anthropic

Context window

1M

Snapshot date

2026-10-13

Knowledge cutoff

Not disclosed

Reference catalog ID

anthropic/claude-sonnet-5.5

When to pick Claude Sonnet 5.5

Claude Sonnet 5.5 is worth reaching for when you need a route scoring in the top quarter on the published intelligence index. The conditions below are the ones its own numbers support.

Each condition below is derived from this model's own values in the 2026-10-13 snapshot, compared only against models publishing the same field.

• Reach for it when answer quality matters more than unit cost. It scores 56.0 on the Artificial Analysis intelligence index, above three quarters of the 119 models carrying that field in the 2026-10-13 snapshot.
• Reach for it when the input includes images. The snapshot records image input, so screenshots, scans, and diagrams can be sent directly instead of described.
• Reach for it when the model has to call tools. Tool calling is recorded in the snapshot, so this route can drive an agent loop rather than only answer in prose.
• Look elsewhere when the request is trivial and latency-sensitive. Reasoning is mandatory on this route and cannot be turned off, so short factual requests still pay reasoning tokens and reasoning latency.

Context, modalities, and identity

Claude Sonnet 5.5 accepts text, image, and file and returns text. The snapshot records agentic, coding, file input, prompt caching, reasoning, reasoning controls, structured output, text generation, tool calling, tools, vision, web search, and web search pricing as capabilities or interfaces.

Model developer

Anthropic

Kendr route provider

Anthropic

Context window

1M

Maximum output

128,000 tokens

Input modalities

text, image, and file

Output modalities

text

Knowledge cutoff

Not disclosed

Model overview

Claude Sonnet 5.5 is Anthropic's Sonnet-class model for well-scoped everyday work, succeeding Claude Sonnet 5 as a direct upgrade. It is especially strong at building features, fixing bugs, and producing polished documents, slides, and spreadsheets, and it writes and communicates more clearly than its predecessor. Thinking is always on, so effort is the main lever for trading off depth, latency, and cost, and lower effort settings keep it responsive for everyday agentic loops.

Reference model ID

anthropic/claude-sonnet-5.5

Canonical version

anthropic/claude-sonnet-5.5-20260928

Hugging Face ID

Not separately documented

Capabilities and supported controls

Capabilities and parameters are reported from the dated catalog and source records; their presence does not guarantee identical behavior across every provider route.

Supported parameters

include_reasoning, max_completion_tokens, max_tokens, reasoning, reasoning_effort, response_format, stop, structured_outputs, tool_choice, tools, verbosity

• agentic
• coding
• file input
• prompt caching
• reasoning
• reasoning controls
• structured output
• text generation
• tool calling
• tools
• vision
• web search
• web search pricing

Dated pricing snapshot

The dated reference snapshot lists $2 input and $10 output per million tokens. Cached input is $0.1 per million tokens. The separately published provider-route reference is $2 / $10 (Standard global inference; $0.10/M cache read; live route quote applies).

Reference figures are dated 2026-10-13; the live Kendr quote can differ by selected provider route, context tier, caching, tools, region, and current rate card.

Price date

2026-10-13

Input

$2 per 1M tokens

Cached input

$0.1 per 1M tokens

Output

$10 per 1M tokens

Provider routes, performance, and uptime

The snapshot retains 8 provider endpoints. Provider prices, context limits, p50 performance, and uptime can differ by route and are not Kendr guarantees.

Active provider endpoints

8

Best p50 latency

0.73 s

Best p50 throughput

108 tok/s

Availability with routing

99.96% over the sampled window

Availability without routing

96.48% over the sampled window

Performance date

2026-10-13

Benchmark evidence and limitations

The 2026-10-13 snapshot includes 1 Artificial Analysis index, 6 Design Arena categories, and AutoExacto results for 9 provider observations. Publisher-reported launch results are labeled and are not presented as Kendr measurements; scores from different suites are not treated as interchangeable.

Third-party catalog fields normalized from the cited model dataset; benchmark methodology and coverage differ by source.

Intelligence Index

56

AutoExacto coverage

9 provider observations over 32 days

AutoExacto provider benchmarks

Rolling provider observations from the cited third-party benchmark view. The lookback is 32 days; GPQA Diamond and TAU-Bench Airline measure different abilities and should not be blended into one score.

Popularity and market context

Claude Sonnet 5.5 ranked #13 in the cited trailing-7-day third-party catalog usage dataset as of 2026-10-13. Observed within the cited trailing-7-day third-party catalog usage dataset; this is not global AI market share.

Third-party catalog rank

#13

Global market share

Not inferred

Observation date

2026-10-13

OpenAI-compatible API example

This example applies to the published Kendr alias on this hosted profile. Check the live public catalog before use.

curl https://api.kendr.org/v1/chat/completions \
  -H "Authorization: Bearer $KENDR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"kc-claude-sonnet-5-5","messages":[{"role":"user","content":"Hello"}]}'

Frequently asked questions

Sources and evidence dates

1. Claude Sonnet 5.5 third-party catalog record (catalog, checked 2026-10-13)
2. Third-party model catalog methodology (methodology, checked 2026-10-13)
3. Anthropic official model documentation (primary, checked 2026-10-13)
4. Artificial Analysis capability indices methodology (benchmark, checked 2026-10-13)
5. Design Arena leaderboard and methodology (benchmark, checked 2026-10-13)
6. Claude Sonnet 5.5 third-party catalog record (benchmark, checked 2026-10-13)
7. Claude Sonnet 5.5 provider or route reference (primary, checked 2026-10-13)