Investment pies

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

Annotations already declare readOnlyHint and idempotentHint, and the description reinforces this by stating 'This server is read-only and cannot create or change a pie.' It also explains the return content (invested value, current value, result, progress), which is useful given no output schema. However, it doesn't mention limits like pagination or error conditions, though these are not critical for a simple listing.

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 two sentences and every word adds value: it explains the resource, the returned data, the sibling tool for details, and the read-only nature. It is front-loaded with the core purpose and has no filler or repetition.

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 simplicity (no parameters, no output schema, clear read-only behavior supported by annotations), the description provides complete context: what it returns, how it relates to the sibling tool, and that it cannot modify anything. There are no significant gaps.

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?

The tool has zero parameters, so the schema trivially covers 100% and there is nothing for the description to compensate. The baseline for zero parameters is 4, and the description appropriately focuses on what is returned rather than parameter syntax.

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 ('Returns') and a clear resource ('the account's pies'), and defines what pies are (named baskets of instruments with target allocations). It also distinguishes itself from the sibling tool t212_get_pie by noting that the sibling provides the instruments inside a specific pie.

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 explicitly says 'Use t212_get_pie for the instruments inside a specific pie', providing an alternative and when to use it. It also implies when to use this tool (when you need an overview of pies), making the usage context clear.

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