get_portfolio_breakdown

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

With no annotations, the description must disclose behavioral traits. It reveals that the tool is premium-gated, requires an API key, and returns slices with value, count, and share. However, it does not state whether the tool is read-only (assumed but not explicit), mention rate limits, or describe any non-obvious side effects.

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 concise with four short sentences, each adding distinct information. The first sentence front-loads the core purpose. No unnecessary words. Could be slightly more structured, but overall efficient.

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?

No output schema is provided, so the description should describe the return format clearly. It states each slice has value, count, and share, but does not specify the overall structure (e.g., array, nested object) or include examples. Adequate but not fully complete.

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 coverage is 100%, so the schema already describes both parameters. The description repeats some schema details (e.g., cost-basis buckets, color identity grouping) but adds no new semantic information beyond what the schema provides. Baseline score of 3 is appropriate.

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 specifies the action ('Get'), the resource ('collection value'), and the output shape ('broken down by a dimension into slices with value, count, and share'). It distinguishes from the sibling tool get_portfolio_breakdown_cards by mentioning drill-down, making the purpose clear and differentiated.

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 states 'Premium-gated' and 'Requires IWMM_API_KEY' as prerequisites. It also references get_portfolio_breakdown_cards for drilling into one slice, providing context on when to use an alternative. However, it does not explicitly exclude other scenarios or compare with get_portfolio_summary.

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