From 15aa9c6c0283475bcf0e1098c15d3f532fefe177 Mon Sep 17 00:00:00 2001 From: Jaewon Lee Date: Mon, 4 May 2026 13:23:47 -0700 Subject: [PATCH 1/2] Add constraints and future outlook for speed preference --- explainers/summarizer-preference-param.md | 2 +- index.bs | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/explainers/summarizer-preference-param.md b/explainers/summarizer-preference-param.md index 4c4dd36..552ddb0 100644 --- a/explainers/summarizer-preference-param.md +++ b/explainers/summarizer-preference-param.md @@ -28,7 +28,7 @@ dictionary SummarizerCreateCoreOptions { ``` * **`"auto"`:** It is implementation-defined how to balance execution speed with summarization capability. The implementation MAY dynamically adjust its internal processing based on the user agent's environment, system constraints, or context. -* **`"speed"`:** The implementation SHOULD prioritize low latency and fast execution. This approach prioritizes performance, which may limit the summarization capability, potentially resulting in less nuanced extraction or simpler synthesis of the source text. +* **`"speed"`:** The implementation SHOULD prioritize low latency and fast execution. This approach prioritizes performance, which may limit the summarization capability, potentially resulting in less nuanced extraction or simpler synthesis of the source text. The `"speed"` preference is constrained to cases where the language is English, the format is `"plain-text"`, the type is `"tldr"` or `"key-points"`, and the length is `"short"` or `"medium"`. These constraints represent initial implementation limitations; it is anticipated that future iterations will expand support to a wider range of options as optimized models evolve. * **`"capability"`:** The implementation SHOULD prioritize the comprehensiveness and coherence of the summarization, and a model that offers more flexibility in terms of summary types and other configurable options. This approach focuses on accurately capturing subtle context and producing highly refined summaries, which may result in higher latency and slower execution speeds. ## Conflicting Constraints and Routing Fallbacks diff --git a/index.bs b/index.bs index 1f1001b..3f9fc77 100644 --- a/index.bs +++ b/index.bs @@ -622,6 +622,7 @@ This section gives normative guidance on how the implementation of [=summarize=] "speed"

The implementation should prioritize low latency and fast execution. This approach prioritizes performance, which may limit the summarization capability, potentially resulting in less nuanced extraction or simpler synthesis of the source text.

+

The "speed" preference is constrained to cases where the language is English, the format is "plain-text", the type is "tldr" or "key-points", and the length is "short" or "medium". These constraints represent initial implementation limitations; it is anticipated that future iterations will expand support to a wider range of options as optimized models evolve.

"capability" From 3ee855ea123fdff3b61d043e15ca1947e7eaaff2 Mon Sep 17 00:00:00 2001 From: Jaewon Lee Date: Mon, 4 May 2026 13:39:32 -0700 Subject: [PATCH 2/2] address offline comments --- explainers/summarizer-preference-param.md | 10 +++++++++- index.bs | 1 - 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/explainers/summarizer-preference-param.md b/explainers/summarizer-preference-param.md index 552ddb0..692b255 100644 --- a/explainers/summarizer-preference-param.md +++ b/explainers/summarizer-preference-param.md @@ -28,9 +28,17 @@ dictionary SummarizerCreateCoreOptions { ``` * **`"auto"`:** It is implementation-defined how to balance execution speed with summarization capability. The implementation MAY dynamically adjust its internal processing based on the user agent's environment, system constraints, or context. -* **`"speed"`:** The implementation SHOULD prioritize low latency and fast execution. This approach prioritizes performance, which may limit the summarization capability, potentially resulting in less nuanced extraction or simpler synthesis of the source text. The `"speed"` preference is constrained to cases where the language is English, the format is `"plain-text"`, the type is `"tldr"` or `"key-points"`, and the length is `"short"` or `"medium"`. These constraints represent initial implementation limitations; it is anticipated that future iterations will expand support to a wider range of options as optimized models evolve. +* **`"speed"`:** The implementation SHOULD prioritize low latency and fast execution. This approach prioritizes performance, which may limit the summarization capability, potentially resulting in less nuanced extraction or simpler synthesis of the source text. * **`"capability"`:** The implementation SHOULD prioritize the comprehensiveness and coherence of the summarization, and a model that offers more flexibility in terms of summary types and other configurable options. This approach focuses on accurately capturing subtle context and producing highly refined summaries, which may result in higher latency and slower execution speeds. +> [!NOTE] +> **Implementation Note (Non-Normative):** The following constraints apply specifically to **Chrome's current implementation** of the `"speed"` preference and are not part of the API specification itself: +> * **Language:** `en` (English) +> * **Output Format:** `"plain-text"` +> * **Output Type:** `"tldr"` or `"key-points"` +> * **Output Length:** `"short"` or `"medium"` +> These constraints represent initial implementation limitations in Chrome. It is anticipated that future iterations will expand support to a wider range of options as optimized models evolve. + ## Conflicting Constraints and Routing Fallbacks The preference parameter acts as a strong hint to the implementation, rather than a strict guarantee. In scenarios where a developer's performance preference conflicts with a hard functional requirement, the implementation MUST prioritize the functional requirement. diff --git a/index.bs b/index.bs index 3f9fc77..1f1001b 100644 --- a/index.bs +++ b/index.bs @@ -622,7 +622,6 @@ This section gives normative guidance on how the implementation of [=summarize=] "speed"

The implementation should prioritize low latency and fast execution. This approach prioritizes performance, which may limit the summarization capability, potentially resulting in less nuanced extraction or simpler synthesis of the source text.

-

The "speed" preference is constrained to cases where the language is English, the format is "plain-text", the type is "tldr" or "key-points", and the length is "short" or "medium". These constraints represent initial implementation limitations; it is anticipated that future iterations will expand support to a wider range of options as optimized models evolve.

"capability"