fix(initialization): accept 204 in addition to 202 on initialize - #497

Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom
gpeal:gpeal/allow-204
Oct 22, 2025
Merged

fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom
gpeal:gpeal/allow-204

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@gpeal

@gpealgpeal commented Oct 22, 2025

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Motivation and Context

Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.

The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.

How Has This Been Tested?

Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03

Breaking Changes

None

Types of changes

  • Bug fix (non-breaking change which fixes an issue)
  • New feature (non-breaking change which adds functionality)
  • Breaking change (fix or feature that would cause existing functionality to change)
  • Documentation update

Checklist

  • I have read the MCP Documentation
  • My code follows the repository's style guidelines
  • New and existing tests pass locally
  • I have added appropriate error handling
  • I have added or updated documentation as needed

@github-actionsgithub-actionsBot added T-core Core library changes T-transport Transport layer changes labels Oct 22, 2025
@gpealgpeal mentioned this pull request Oct 22, 2025
Closed
@alexhancock
alexhancock merged commit 3822d9d into modelcontextprotocol:mainOct 22, 2025
11 checks passed
@github-actionsgithub-actionsBot mentioned this pull request Oct 22, 2025
Merged
@gpealgpeal mentioned this pull request Oct 22, 2025
Merged
gpeal added a commit to openai/codex that referenced this pull request Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit to JeffCarpenter/codex that referenced this pull request Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit to DioNanos/codex-termux that referenced this pull request Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit to nextlw/elai_codex that referenced this pull request Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit to earthlings-dev/codex that referenced this pull request Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit to earthlings-dev/rmcp that referenced this pull request Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot pushed a commit to agogo233/Ecode that referenced this pull request Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit to AIALRA-0/codex-turn-engine that referenced this pull request Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit to alo-labs/kay that referenced this pull request Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
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}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

Copy link


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Contributor
Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
pushed a commit
to agogo233/Ecode
that referenced
this pull request
Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
to AIALRA-0/codex-turn-engine
that referenced
this pull request
Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
to alo-labs/kay
that referenced
this pull request
Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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@gpeal@alexhancock

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

Copy link


Copy Markdown

Contributor
Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
pushed a commit
to agogo233/Ecode
that referenced
this pull request
Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
to AIALRA-0/codex-turn-engine
that referenced
this pull request
Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
to alo-labs/kay
that referenced
this pull request
Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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@alexhancockalexhancockalexhancock approved these changes

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T-coreCore library changesT-transportTransport layer changes

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2 participants

@gpeal@alexhancock

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

Copy link


Copy Markdown

Contributor
Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
pushed a commit
to agogo233/Ecode
that referenced
this pull request
Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
to AIALRA-0/codex-turn-engine
that referenced
this pull request
Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
to alo-labs/kay
that referenced
this pull request
Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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Reviewers

@alexhancockalexhancockalexhancock approved these changes

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T-coreCore library changesT-transportTransport layer changes

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2 participants

@gpeal@alexhancock

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

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Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
pushed a commit
to agogo233/Ecode
that referenced
this pull request
Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
to AIALRA-0/codex-turn-engine
that referenced
this pull request
Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
to alo-labs/kay
that referenced
this pull request
Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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@gpeal@alexhancock

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

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Contributor
Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
pushed a commit
to agogo233/Ecode
that referenced
this pull request
Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
to AIALRA-0/codex-turn-engine
that referenced
this pull request
Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
to alo-labs/kay
that referenced
this pull request
Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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2 participants

@gpeal@alexhancock

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

Copy link


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Contributor
Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
pushed a commit
to agogo233/Ecode
that referenced
this pull request
Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
to AIALRA-0/codex-turn-engine
that referenced
this pull request
Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
to alo-labs/kay
that referenced
this pull request
Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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@alexhancockalexhancockalexhancock approved these changes

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T-coreCore library changesT-transportTransport layer changes

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2 participants

@gpeal@alexhancock

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

Skip to content
fix(initialization): accept 204 in addition to 202 on initialize - #497
Merged
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Oct 22, 2025
Merged
fix(initialization): accept 204 in addition to 202 on initialize#497
alexhancock merged 1 commit into
modelcontextprotocol:mainfrom 
gpeal:gpeal/allow-204
Conversation
@gpeal
@gpealgpeal
commented
Oct 22, 2025

Copy link


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Contributor
Motivation and Context
Most MCP servers return a 202 in response to notifications/initialized. However, it seams like some such as the allflow server from openai/codex#5208 return a 204. Other clients such as claude code and npx @modelcontextprotocol/inspector accept 204 so it seems reasonable to do so here.
The spec is ambiguous here from what I can tell. I don't see it explicitly mention that the notification response must be a 202.
How Has This Been Tested?
Test the failing server from openai/codex#5208. It now works.
CleanShot 2025-10-22 at 11 42 03
Breaking Changes
None
Types of changes
  •  Bug fix (non-breaking change which fixes an issue)
  •  New feature (non-breaking change which adds functionality)
  •  Breaking change (fix or feature that would cause existing functionality to change)
  •  Documentation update
Checklist
  •  I have read the MCP Documentation
  •  My code follows the repository's style guidelines
  •  New and existing tests pass locally
  •  I have added appropriate error handling
  •  I have added or updated documentation as needed
@github-actionsgithub-actionsBot
added

T-core
Core library changes
T-transport
Transport layer changes
labels
Oct 22, 2025
@gpealgpeal
mentioned this pull request
Oct 22, 2025

Closed

@alexhancock
alexhancock
merged commit 3822d9d
into
modelcontextprotocol:mainOct 22, 2025

11 checks passed

@github-actionsgithub-actionsBot
mentioned this pull request
Oct 22, 2025
 Merged

@gpealgpeal
mentioned this pull request
Oct 22, 2025
 Merged

gpeal added a commit
to openai/codex
that referenced
this pull request
Oct 24, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
abccd3e
Picks up modelcontextprotocol/rust-sdk#497 which fixes#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
JeffCarpenter pushed a commit
to JeffCarpenter/codex
that referenced
this pull request
Oct 28, 2025
@gpeal@JeffCarpenter
[MCP] Update rmcp to 0.8.3 (openai#5542)
7e76388
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
DioNanos pushed a commit
to DioNanos/codex-termux
that referenced
this pull request
Nov 10, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
3e7cea7
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
willy3087 pushed a commit
to nextlw/elai_codex
that referenced
this pull request
Nov 14, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
37278b6
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/codex
that referenced
this pull request
Dec 2, 2025
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
621c054
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
takumi-earth pushed a commit
to earthlings-dev/rmcp
that referenced
this pull request
Jan 27, 2026
@gpeal
fix: accept 204 in addition to 202 on initialize (modelcontextprotoco…
340da10
…l#497)
monkeycode-aiBot
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Jun 8, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
316f4b2
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
AIALRA-0 pushed a commit
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Jun 10, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (openai#5542)
34fdb70
Picks up modelcontextprotocol/rust-sdk#497 which fixesopenai#5208 by allowing 204 response to MCP initialize notifications instead of just 202.
shafqatevo pushed a commit
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Aug 7, 2026
@gpeal
[MCP] Update rmcp to 0.8.3 (#5542)
875353b
Picks up modelcontextprotocol/rust-sdk#497 which fixes #5208 by allowing 204 response to MCP initialize notifications instead of just 202.
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