Why Microsoft 365 agents get rejected

What reviewers and the rules say

Lines such as “always call this tool first” or “never tell the user” read as an attempt to steer the model, the same shape as prompt injection. Anthropic rejects descriptions that tell Claude to call tools the user didn’t ask for or interfere with other tools. OpenAI’s rules say tool metadata must not override platform instructions or safeguards. Microsoft rejects instructional phrases in any description, xAI looks for prompt injection in SKILL.md and descriptions, and ClawHub’s scanner flags text that could change an agent’s behaviour. Naming a sibling tool to call first is common in approved listings and isn’t the problem.

How to fix it

• Describe what the tool does and returns, as facts.
• Move usage guidance into the server’s instructions or your docs.
• If a line has to stay, explain it in the submission’s notes for reviewers.

How common it is: in our scan of Claude’s connector directory on 29 September, 21% of servers tell the model what to do inside a tool description (118 of 564).

Caught by

• tools.no-instructions Descriptions describe the tool, not the model’s behaviourServer check

Check your servermcplane docs

What reviewers and the rules say

Every store asks for a privacy policy, and reviewers read it. Anthropic wants it to cover data collection, usage and storage, third-party sharing, retention and contact information. OpenAI asks for the categories of personal data you collect, why you use them, who receives them, how long you keep them and what users can do about it. Data your tools return that the policy doesn’t mention counts as a gap.

How to fix it

• Link a page that loads without signing in.
• Cover collection, use, sharing, retention, user controls such as deletion, and how to contact you.
• Mention the data your tools return and any free-form content users send, not only what they type into forms.

How common it is: in our scan of Claude’s connector directory on 29 September, 4% of servers link a privacy policy that doesn’t load (145 of 3,283).

Caught by

• listing.privacy The privacy policy covers what reviewers look forServer check
• listing.privacy-content Free-form content is covered by the privacy policyServer check

Check your servermcplane docs

What reviewers and the rules say

Microsoft rejects agents that do what Copilot already does. Its examples of differentiated value are workflows Copilot can’t do easily, such as creating tickets directly in a ticketing platform, and workflows the agent makes much faster.

How to fix it

• Lead the description with the workflow your agent completes that Copilot can’t.
• Make the sample prompts show that workflow.

Caught by

No script can see this one. A server check rules out the mechanical causes first.

Check your servermcplane docs

What reviewers and the rules say

Each store enforces its own limits, some without telling you until review. ChatGPT’s display name and subtitle stop at 30 characters each, and it takes up to three starter prompts. Claude caps names at 100 characters, one-liners at 200, descriptions at 2,000 and tool names at 64. Microsoft wants three to five prompts per command, none over 128 characters.

How to fix it

• Keep a shorter name for ChatGPT if yours runs past 30 characters.
• Write up to three distinct starter prompts for ChatGPT, without @mentions.
• Rename any tool over 64 characters.

How common it is: in our scan of Claude’s connector directory on 29 September, 3% of servers have a name longer than ChatGPT’s 30 characters (92 of 3,283).

Caught by

• listing.name Display name fits (30 characters)Server check
• listing.claude-name Name for Claude fits (100 characters)Server check
• tools.name-length Tool names are 64 characters or fewerServer check
• listing.prompts Starter prompts are short, unique and free of @mentionsmcplane CLI
• listing.subtitle Subtitle fits (30 characters)mcplane CLI
• listing.one-liner One-liner fits (200 characters)mcplane CLI

Check your servermcplane docs

What reviewers and the rules say

Reviewers run what you give them, as the account you gave them, against your live server: ChatGPT’s five positive and three negative test cases, Microsoft’s sample prompts, or a demo for Grok. A test that names a tool you have since renamed, or expects data that has since changed, reads as a broken app. OpenAI also expects the same test cases to pass on ChatGPT web and mobile.

How to fix it

• In each test case, name only tools the live server has.
• Seed the demo account with the data every test case expects, and check it again right before you submit.
• Record ChatGPT’s video walkthrough in developer mode, and again whenever tools change.
• Give write tools a safe target, so reviewers don’t post to a real account.
• For Grok, be ready to share a short demo of sign-in, OAuth consent and a harmless request.

Caught by

• listing.test-tools Test cases use tools the server hasmcplane CLI
• Demo data matches every test case, checked right before submittingBy hand

Check your servermcplane docs