From 0f173eb8ae049bc484a4e8a63213e49e17d61eab Mon Sep 17 00:00:00 2001
From: Richard Feldman <richard@zed.dev>
Date: Tue, 31 Mar 2026 10:54:52 -0400
Subject: [PATCH] Remove deprecated 1M context beta header for Sonnet 4.5
 (#52767)

The `CONTEXT_1M_BETA_HEADER` (`context-1m-2025-08-07`) is deprecated for
Sonnet 4 and 4.5. This removes the constant from the anthropic crate and
the match arm in `beta_headers()` that sent it for
`ClaudeSonnet4_5_1mContext`.

Note: The bedrock crate still has its own copy of this constant, used
when the user-configurable `allow_extended_context` setting is enabled.
That may warrant a separate cleanup.

Closes AI-114

Release Notes:

- N/A
---
 crates/anthropic/src/anthropic.rs | 28 ++--------------------------
 1 file changed, 2 insertions(+), 26 deletions(-)

diff --git a/crates/anthropic/src/anthropic.rs b/crates/anthropic/src/anthropic.rs
index 236358e3a8e3d955435d685b70f49ea6f644d86d..5d7790b86b09853e22436252fcde1bebf5feff9b 100644
--- a/crates/anthropic/src/anthropic.rs
+++ b/crates/anthropic/src/anthropic.rs
@@ -15,8 +15,6 @@ pub mod batches;
 
 pub const ANTHROPIC_API_URL: &str = "https://api.anthropic.com";
 
-pub const CONTEXT_1M_BETA_HEADER: &str = "context-1m-2025-08-07";
-
 #[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 #[derive(Clone, Debug, Default, Serialize, Deserialize, PartialEq)]
 pub struct AnthropicModelCacheConfiguration {
@@ -85,13 +83,6 @@ pub enum Model {
         alias = "claude-sonnet-4-5-thinking-latest"
     )]
     ClaudeSonnet4_5,
-    #[serde(
-        rename = "claude-sonnet-4-5-1m-context",
-        alias = "claude-sonnet-4-5-1m-context-latest",
-        alias = "claude-sonnet-4-5-1m-context-thinking",
-        alias = "claude-sonnet-4-5-1m-context-thinking-latest"
-    )]
-    ClaudeSonnet4_5_1mContext,
     #[default]
     #[serde(
         rename = "claude-sonnet-4-6",
@@ -158,10 +149,6 @@ impl Model {
             return Ok(Self::ClaudeSonnet4_6);
         }
 
-        if id.starts_with("claude-sonnet-4-5-1m-context") {
-            return Ok(Self::ClaudeSonnet4_5_1mContext);
-        }
-
         if id.starts_with("claude-sonnet-4-5") {
             return Ok(Self::ClaudeSonnet4_5);
         }
@@ -189,7 +176,6 @@ impl Model {
             Self::ClaudeOpus4_6 => "claude-opus-4-6-latest",
             Self::ClaudeSonnet4 => "claude-sonnet-4-latest",
             Self::ClaudeSonnet4_5 => "claude-sonnet-4-5-latest",
-            Self::ClaudeSonnet4_5_1mContext => "claude-sonnet-4-5-1m-context-latest",
             Self::ClaudeSonnet4_6 => "claude-sonnet-4-6-latest",
             Self::ClaudeHaiku4_5 => "claude-haiku-4-5-latest",
             Self::Claude3Haiku => "claude-3-haiku-20240307",
@@ -205,7 +191,7 @@ impl Model {
             Self::ClaudeOpus4_5 => "claude-opus-4-5-20251101",
             Self::ClaudeOpus4_6 => "claude-opus-4-6",
             Self::ClaudeSonnet4 => "claude-sonnet-4-20250514",
-            Self::ClaudeSonnet4_5 | Self::ClaudeSonnet4_5_1mContext => "claude-sonnet-4-5-20250929",
+            Self::ClaudeSonnet4_5 => "claude-sonnet-4-5-20250929",
             Self::ClaudeSonnet4_6 => "claude-sonnet-4-6",
             Self::ClaudeHaiku4_5 => "claude-haiku-4-5-20251001",
             Self::Claude3Haiku => "claude-3-haiku-20240307",
@@ -221,7 +207,6 @@ impl Model {
             Self::ClaudeOpus4_6 => "Claude Opus 4.6",
             Self::ClaudeSonnet4 => "Claude Sonnet 4",
             Self::ClaudeSonnet4_5 => "Claude Sonnet 4.5",
-            Self::ClaudeSonnet4_5_1mContext => "Claude Sonnet 4.5 (1M context)",
             Self::ClaudeSonnet4_6 => "Claude Sonnet 4.6",
             Self::ClaudeHaiku4_5 => "Claude Haiku 4.5",
             Self::Claude3Haiku => "Claude 3 Haiku",
@@ -239,7 +224,6 @@ impl Model {
             | Self::ClaudeOpus4_6
             | Self::ClaudeSonnet4
             | Self::ClaudeSonnet4_5
-            | Self::ClaudeSonnet4_5_1mContext
             | Self::ClaudeSonnet4_6
             | Self::ClaudeHaiku4_5
             | Self::Claude3Haiku => Some(AnthropicModelCacheConfiguration {
@@ -263,9 +247,7 @@ impl Model {
             | Self::ClaudeSonnet4_5
             | Self::ClaudeHaiku4_5
             | Self::Claude3Haiku => 200_000,
-            Self::ClaudeOpus4_6 | Self::ClaudeSonnet4_5_1mContext | Self::ClaudeSonnet4_6 => {
-                1_000_000
-            }
+            Self::ClaudeOpus4_6 | Self::ClaudeSonnet4_6 => 1_000_000,
             Self::Custom { max_tokens, .. } => *max_tokens,
         }
     }
@@ -276,7 +258,6 @@ impl Model {
             Self::ClaudeOpus4_5
             | Self::ClaudeSonnet4
             | Self::ClaudeSonnet4_5
-            | Self::ClaudeSonnet4_5_1mContext
             | Self::ClaudeSonnet4_6
             | Self::ClaudeHaiku4_5 => 64_000,
             Self::ClaudeOpus4_6 => 128_000,
@@ -295,7 +276,6 @@ impl Model {
             | Self::ClaudeOpus4_6
             | Self::ClaudeSonnet4
             | Self::ClaudeSonnet4_5
-            | Self::ClaudeSonnet4_5_1mContext
             | Self::ClaudeSonnet4_6
             | Self::ClaudeHaiku4_5
             | Self::Claude3Haiku => 1.0,
@@ -327,7 +307,6 @@ impl Model {
                 | Self::ClaudeOpus4_6
                 | Self::ClaudeSonnet4
                 | Self::ClaudeSonnet4_5
-                | Self::ClaudeSonnet4_5_1mContext
                 | Self::ClaudeSonnet4_6
                 | Self::ClaudeHaiku4_5
         )
@@ -341,9 +320,6 @@ impl Model {
         let mut headers = vec![];
 
         match self {
-            Self::ClaudeSonnet4_5_1mContext => {
-                headers.push(CONTEXT_1M_BETA_HEADER.to_string());
-            }
             Self::Custom {
                 extra_beta_headers, ..
             } => {