MQScript MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden for behavioral disclosure. While 'Get substring' implies a read-only operation, the description doesn't address potential edge cases (e.g., what happens if start position is out of bounds, if length extends beyond string, or if negative values are used). It also doesn't mention that the result is stored in a variable (as indicated by the resultVariable parameter), which is a key behavioral aspect. The description is minimal and lacks operational context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise at just 5 words ('Get substring from specified position'). It's front-loaded with the core functionality and contains no wasted words. While it may be too brief for optimal tool understanding, it earns full marks for conciseness as every word contributes directly to stating the tool's purpose.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a string manipulation tool with 4 parameters and no annotations or output schema, the description is inadequate. It doesn't explain the 1-based indexing (mentioned in schema but not emphasized), doesn't clarify the default behavior when length is -1, doesn't mention the variable storage mechanism, and provides no examples or context about return values. Given the complexity of substring extraction with position and length parameters, more guidance is needed for effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with all four parameters well-documented in the schema itself (text, start, length, resultVariable). The description adds no additional parameter information beyond what the schema provides - it doesn't explain the relationship between parameters or provide usage examples. With complete schema coverage, the baseline score of 3 is appropriate since the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Get substring from specified position' clearly states the verb ('Get substring') and resource ('from specified position'), making the purpose understandable. However, it doesn't distinguish this tool from sibling string manipulation tools like 'mqscript_left', 'mqscript_right', or 'mqscript_instr', which all work with substrings or string positions. The description is functional but generic within this context.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With siblings like 'mqscript_left' (get left substring), 'mqscript_right' (get right substring), and 'mqscript_instr' (find substring position), there's clear overlap in functionality, but the description doesn't explain when this mid-position extraction is preferred over those other approaches. No usage context or exclusions are mentioned.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.