get_instances

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

With no annotations provided, the description carries the full burden and does so excellently. It explicitly states 'Read-only' and reveals the return shape, including the conditional behavior of the 'scope' field when GRAMPS_MCP_INSTANCES is unset. This leaves little ambiguity about side effects or expected results.

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 tightly structured with a header, args section, and returns section. Every line contributes meaningful information, and the core purpose and read-only nature are front-loaded. No unnecessary elaboration exists.

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?

Given the tool's zero-parameter complexity, no output schema, and no annotations, the description is fully sufficient. It provides the return dict shapeaine, the meaning of the fields, and the fallback behavior. No critical operational detail is missing.

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?

There are zero parametersholistic, so the baseline of 4 applies. The description's 'Args: (none)' matches the empty schema and adds no misleading expectations. Parameter semantics are not a concern for this tool.

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 specific verb and resource: 'List the configured target instances.' This accurately reflects the tool's function and clearly differentiates it from the sibling management tools like manage_person or manage_place. The 'Read-only' qualifier further distinguishes it from mutating operations.

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 implies when to use the tool: whenever an agent needs to see the configured target instances or discover the scope. However, it does not explicitly state usage context or mention alternatives, relying mostly on the self-evident nature of a zero-parameter read-only query.

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