Compare funds

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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds real substance by disclosing the comparison surface the agent will get back (returns for every period, allocation, manager), which goes beyond what the annotations state.

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?

Two short sentences with zero filler; the capability statement is front-loaded and the usage routing follows. Every clause carries information.

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?

With one fully documented parameter, no output schema and complete annotations, the description covers what an agent needs to select and call it. Minor gaps remain: nothing about result ordering, or behavior when an id is invalid or the array bounds are violated.

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% and the schema already documents the 'regNo' / 'regNo-groupId' format with examples. The description still earns credit by adding provenance: 'Ids are the reg_no (and group_id) of search rows', telling the agent where to obtain valid values.

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?

States a specific verb and resource ('Put 2 to 8 funds side by side') and enumerates exactly which attributes are compared (type, size, NAV, returns, allocation, manager). That level of detail makes it unmistakably distinct from the single-fund sibling fp_fund without needing to name it.

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?

'Use after fp_search_funds when the user is choosing between funds' gives both a prerequisite and the decision context that selects this tool. It does not state a negative case (e.g. use fp_fund for a single fund), so it falls just short of full when/when-not coverage.

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