[BUG] API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"tools.26.custom.name: String should match pattern '^[a-zA-Z0-9_-]{1,64}$'"}}
Status Fixed / completed
Maintainer reply None cached
Activity 6 comments · opened Apr 23, 2025 · closed Apr 25, 2025
Environment
- Platform (select one):
- Anthropic API
- Claude CLI version: 0.2.79
- Operating System: Mac OS
- Terminal: Zsh
Bug Description
I recently added context7 mcp server which is when this issue started happening. This is the mcp-server.json in my local project. It's unclear as to where the global settings are stored.
{
"mcpServers": {
"filesystem": {
"command": "npx",
"args": [
"-y",
"@modelcontextprotocol/server-filesystem",
"/Users/{username}/PycharmProjects/",
"/Users/{username}/Documents/"
]
},
"sequential-thinking": {
"command": "npx",
"args": [
"-y",
"@modelcontextprotocol/server-sequential-thinking",
"/Users/{username}/PycharmProjects/servers/src/sequentialthinking"
]
},
"memory": {
"command": "npx",
"args": [
"-y",
"@modelcontextprotocol/server-memory"
]
},
"github.com/modelcontextprotocol/servers/tree/main/src/puppeteer": {
"command": "npx",
"args": [
"-y",
"@modelcontextprotocol/server-puppeteer"
],
"disabled": false,
"autoApprove": []
},
"github.com/JetBrains/mcp-jetbrains": {
"command": "npx",
"args": [
"-y",
"@jetbrains/mcp-proxy"
],
"disabled": false,
"autoApprove": []
},
"github.com/zcaceres/fetch-mcp": {
"command": "node",
"args": [
"/Users/{davidandrews}/PycharmProjects/fetch-mcp/dist/index.js"
],
"disabled": false,
"autoApprove": []
},
"github.com/upstash/context7-mcp": {
"command": "npx",
"args": [
"-y",
"@upstash/context7-mcp@latest"
],
"disabled": false,
"autoApprove": []
}
}
}
## Steps to Reproduce
1. Update `mcp-server.sjon` in local project.
2. Add literally any text to the prompt.
## Expected Behavior
I expect it to handle the prompt properly without an error.
## Actual Behavior
3. Receive the error: `API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"tools.26.custom.name: String should match pattern '^[a-zA-Z0-9_-]{1,64}$'"}}
`
## Additional Context
I'd love to know where Claude Coder's global mcp settings.json is stored...
6 Comments
Hmm
same for me after installing context7.. but I removed it and claude still gives me this error..
Same here
Still was happening to me today with version
1.0.7 (Claude Code)I was able to fix on my install, by going to ~/.claude.json and removing context7 from everywhere I had it installed. Also check the .mcp.json file (if it exists) in whatever dir you're running claude code.One data point: the presence of an absolute path in the command was causing this issue. I had
/Users/name/.local/bin/commandas the mcp command to run, changing this tobash -lc commandfixed it.This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.