Public executeToolCall routes MCPL tools by first matching prefix, not by listing owner / longest prefix

Found while reviewing connectome-host #191; pre-existing on main (e457abd, v0.21.0) and unchanged by #220.

What happens

executeToolCallFrom (the path behind the public executeToolCall, used for promise-based and programmatic callers) scans the server configs and takes the first whose prefix matches:

agent-framework/src/framework.ts

Lines 10905 to 10913 in e457abd

    
           // Check if this is an MCPL-prefixed tool 
        
           const prefix = call.name.split('--').slice(0, -1).join('--'); 
        
           const serverConfigs = this.mcplServerConfigs; 
        
           for (const [, config] of serverConfigs) { 
        
             const toolPrefix = config.toolPrefix ?? `mcpl--${config.id}`; 
        
             if (call.name.startsWith(toolPrefix + '--')) { 
        
               return this.executeMcplToolCall(call, config); 
        
             } 
        
           }

Model dispatch uses resolveMcplTool, which prefers the server that actually listed the tool and otherwise the longest matching prefix:

agent-framework/src/framework.ts

Lines 11956 to 11965 in e457abd

    
           private resolveMcplTool(toolName: string): [string, string] | null { 
        
             const listedBy = this.mcplToolServers?.get(toolName); 
        
             let best: [string, string] | null = null; 
        
             for (const [prefix, serverId] of this.mcplPrefixMap ?? []) { 
        
               if (!toolName.startsWith(prefix + '--')) continue; 
        
               if (serverId === listedBy) return [serverId, prefix]; 
        
               if (!best || prefix.length > best[1].length) best = [serverId, prefix]; 
        
             } 
        
             return best; 
        
           }

Failure

With two servers whose prefixes nest (foo and foo--bar), a call to foo--bar--x resolves to ['inner', 'foo--bar'] on the model path, but the public path invokes server outer with tool bar--x. The same tool name runs a different server operation depending on which dispatcher it entered through. An in-memory RPC probe reproduced exactly that.

Needs nested prefixes to bite, so low frequency, but it is a wrong-target dispatch when it does.

Suggested direction

Use resolveMcplTool in executeToolCallFrom as well, and strip the resolved prefix when deriving the server-side tool name.

fix(mcpl): a programmatic tool call reaches the server the model's ca…

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Public executeToolCall routes MCPL tools by first matching prefix, not by listing owner / longest prefix #227

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	// Check if this is an MCPL-prefixed tool
	const prefix = call.name.split('--').slice(0, -1).join('--');
	const serverConfigs = this.mcplServerConfigs;
	for (const [, config] of serverConfigs) {
	const toolPrefix = config.toolPrefix ?? `mcpl--${config.id}`;
	if (call.name.startsWith(toolPrefix + '--')) {
	return this.executeMcplToolCall(call, config);
	}
	}

	private resolveMcplTool(toolName: string): [string, string] \| null {
	const listedBy = this.mcplToolServers?.get(toolName);
	let best: [string, string] \| null = null;
	for (const [prefix, serverId] of this.mcplPrefixMap ?? []) {
	if (!toolName.startsWith(prefix + '--')) continue;
	if (serverId === listedBy) return [serverId, prefix];
	if (!best \|\| prefix.length > best[1].length) best = [serverId, prefix];
	}
	return best;
	}

Public executeToolCall routes MCPL tools by first matching prefix, not by listing owner / longest prefix #227

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