Echoes all input parameters back as JSON so you can verify argument structure and value types in MCP test calls.
Echo all parameters back as JSON.
| Name | Required | Description | Default |
|---|---|---|---|
| int_param | Yes | ||
| obj_param | Yes | ||
| str_param | Yes | ||
| bool_param | Yes | ||
| list_param | Yes | ||
| float_param | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v1.0.4Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It discloses only that parameters come back as JSON; it says nothing about side effects, required permissions, error behavior (contrast sibling echo_error), or whether inputs are returned unmodified by type.
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?
A single short sentence with zero filler and the key action front-loaded. It is efficient, though arguably terse for a six-parameter tool.
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?
An output schema exists, so return values need not be described, and for a trivial echo tool the description is nearly sufficient. The remaining gap is that six required parameters at 0% schema coverage are left entirely unexplained.
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 0% and there are six required parameters, so the description is the only place semantics could be added. 'All parameters' adds only the idea that inputs are echoed as-is, with no explanation of any of the six typed parameters beyond their self-evident names.
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 states a clear verb (echo) and resource (all parameters) and specifies the output form (JSON). What it does is unambiguous on its own, but it does not distinguish itself from the many sibling echo variants (echo, echo_types, echo_nested, echo_multiple), which is the main gap.
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?
There is no guidance on when to use this tool versus echo, echo_types, echo_nested, or echo_error. The only implied usage is as a passthrough/test tool, and no conditions or exclusions are stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.