Skip to content

Anthropic: extended thinking config not captured in span metadata #107

Closed
Feature
#110
Closed
Anthropic: extended thinking config not captured in span metadata#107
Feature
#110
Assignees
AbhiPrasad
Labels
integration: anthropic

Description

@AbhiPrasad
Abhijeet Prasad (AbhiPrasad)
opened on Mar 20, 2026

Gap

When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.

The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.

This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.

What is missing

Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.

Braintrust docs status

not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.

Upstream sources

Local files inspected

  • py/src/braintrust/wrappers/anthropic.py:
    • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
    • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
  • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration

Metadata

Metadata

Assignees

Labels

integration: anthropic

Type

Feature

Projects

No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions

    , 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
     blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
    Skip to content
    Anthropic: extended thinking config not captured in span metadata #107
    Closed
    Feature
    #110
    Closed
    Anthropic: extended thinking config not captured in span metadata#107
    Feature
    #110
    Assignees
    AbhiPrasad
    Labels
    integration: anthropic
    Description
    @AbhiPrasad
    Abhijeet Prasad (AbhiPrasad)
    opened on Mar 20, 2026
    Gap
    When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
    The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
    This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
    What is missing
    Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
    Braintrust docs status
    not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
    Upstream sources
    Local files inspected
    • py/src/braintrust/wrappers/anthropic.py:

      • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
      • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
    • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
    Metadata
    Metadata
    Assignees
    Labels
    integration: anthropic
    Type
    Feature
    Projects
    No projects
      Milestone
      No milestone
      Relationships
      None yet
      Development
      No branches or pull requests
      Issue actions
      
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
      Skip to content
      Anthropic: extended thinking config not captured in span metadata #107
      Closed
      Feature
      #110
      Closed
      Anthropic: extended thinking config not captured in span metadata#107
      Feature
      #110
      Assignees
      AbhiPrasad
      Labels
      integration: anthropic
      Description
      @AbhiPrasad
      Abhijeet Prasad (AbhiPrasad)
      opened on Mar 20, 2026
      Gap
      When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
      The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
      This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
      What is missing
      Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
      Braintrust docs status
      not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
      Upstream sources
      Local files inspected
      • py/src/braintrust/wrappers/anthropic.py:

        • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
        • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
      • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
      Metadata
      Metadata
      Assignees
      Labels
      integration: anthropic
      Type
      Feature
      Projects
      No projects
        Milestone
        No milestone
        Relationships
        None yet
        Development
        No branches or pull requests
        Issue actions
        
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
        Skip to content
        Anthropic: extended thinking config not captured in span metadata #107
        Closed
        Feature
        #110
        Closed
        Anthropic: extended thinking config not captured in span metadata#107
        Feature
        #110
        Assignees
        AbhiPrasad
        Labels
        integration: anthropic
        Description
        @AbhiPrasad
        Abhijeet Prasad (AbhiPrasad)
        opened on Mar 20, 2026
        Gap
        When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
        The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
        This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
        What is missing
        Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
        Braintrust docs status
        not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
        Upstream sources
        Local files inspected
        • py/src/braintrust/wrappers/anthropic.py:

          • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
          • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
        • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
        Metadata
        Metadata
        Assignees
        Labels
        integration: anthropic
        Type
        Feature
        Projects
        No projects
          Milestone
          No milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
          Skip to content
          Anthropic: extended thinking config not captured in span metadata #107
          Closed
          Feature
          #110
          Closed
          Anthropic: extended thinking config not captured in span metadata#107
          Feature
          #110
          Assignees
          AbhiPrasad
          Labels
          integration: anthropic
          Description
          @AbhiPrasad
          Abhijeet Prasad (AbhiPrasad)
          opened on Mar 20, 2026
          Gap
          When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
          The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
          This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
          What is missing
          Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
          Braintrust docs status
          not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
          Upstream sources
          Local files inspected
          • py/src/braintrust/wrappers/anthropic.py:

            • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
            • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
          • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
          Metadata
          Metadata
          Assignees
          Labels
          integration: anthropic
          Type
          Feature
          Projects
          No projects
            Milestone
            No milestone
            Relationships
            None yet
            Development
            No branches or pull requests
            Issue actions
            
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
            Skip to content
            Anthropic: extended thinking config not captured in span metadata #107
            Closed
            Feature
            #110
            Closed
            Anthropic: extended thinking config not captured in span metadata#107
            Feature
            #110
            Assignees
            AbhiPrasad
            Labels
            integration: anthropic
            Description
            @AbhiPrasad
            Abhijeet Prasad (AbhiPrasad)
            opened on Mar 20, 2026
            Gap
            When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
            The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
            This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
            What is missing
            Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
            Braintrust docs status
            not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
            Upstream sources
            Local files inspected
            • py/src/braintrust/wrappers/anthropic.py:

              • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
              • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
            • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
            Metadata
            Metadata
            Assignees
            Labels
            integration: anthropic
            Type
            Feature
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
              Skip to content
              Anthropic: extended thinking config not captured in span metadata #107
              Closed
              Feature
              #110
              Closed
              Anthropic: extended thinking config not captured in span metadata#107
              Feature
              #110
              Assignees
              AbhiPrasad
              Labels
              integration: anthropic
              Description
              @AbhiPrasad
              Abhijeet Prasad (AbhiPrasad)
              opened on Mar 20, 2026
              Gap
              When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
              The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
              This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
              What is missing
              Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
              Braintrust docs status
              not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
              Upstream sources
              Local files inspected
              • py/src/braintrust/wrappers/anthropic.py:

                • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
                • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
              • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
              Metadata
              Metadata
              Assignees
              Labels
              integration: anthropic
              Type
              Feature
              Projects
              No projects
                Milestone
                No milestone
                Relationships
                None yet
                Development
                No branches or pull requests
                Issue actions
                
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
Anthropic: extended thinking config not captured in span metadata · Issue #107 · braintrustdata/braintrust-sdk-python · GitHub
                Skip to content
                Anthropic: extended thinking config not captured in span metadata #107
                Closed
                Feature
                #110
                Closed
                Anthropic: extended thinking config not captured in span metadata#107
                Feature
                #110
                Assignees
                AbhiPrasad
                Labels
                integration: anthropic
                Description
                @AbhiPrasad
                Abhijeet Prasad (AbhiPrasad)
                opened on Mar 20, 2026
                Gap
                When users enable extended thinking via the thinking parameter (e.g., thinking={"type": "enabled", "budget_tokens": 10000}), this configuration is not captured in span metadata. The thinking parameter is absent from METADATA_PARAMS in the Anthropic wrapper.
                The thinking content blocks in the response ARE captured in span.output (since the full content array is logged), and token usage is correct (Anthropic counts thinking tokens within output_tokens). The gap is that the thinking configuration itself — whether it was enabled, the budget, and the type — is invisible in span metadata.
                This matters because extended thinking is a major Anthropic feature (required for Claude Opus, configurable for Sonnet) and users need visibility into how they configured it across different traces.
                What is missing
                Add "thinking" to METADATA_PARAMS (line 30 of anthropic.py) so the thinking configuration is logged as span metadata.
                Braintrust docs status
                not_found — the Anthropic integration page at braintrust.dev/docs/integrations/ai-providers/anthropic does not mention extended thinking.
                Upstream sources
                Local files inspected
                • py/src/braintrust/wrappers/anthropic.py:

                  • METADATA_PARAMS (line 30-40): includes model, max_tokens, temperature, top_k, top_p, stop_sequences, tool_choice, tools, stream — but NOT thinking
                  • _start_span() extracts only params listed in METADATA_PARAMS into span metadata
                • py/src/braintrust/wrappers/test_anthropic.py — no test cases for extended thinking configuration
                Metadata
                Metadata
                Assignees
                Labels
                integration: anthropic
                Type
                Feature
                Projects
                No projects
                  Milestone
                  No milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions