compare_funds

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

With no annotations, the description carries the full burden. It does useful work by disclosing the returned metrics, the 1–5 fund cap, and the null-if-too-new behavior, but it never states that the call is read-only, what happens if more than 5 codes are passed, or how lookup failures are reported.

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 sentences, front-loaded with the core action and scope, then a compact enumeration of what each fund contributes. No filler and no repetition of schema metadata.

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 the description need not enumerate return fields, yet the required scheme_codes argument and the over-limit error path remain undocumented. Adequate for a simple read tool, but the required-parameter gap keeps it at minimum viable.

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 0%, so the description should compensate more than it does. It explains risk_years as the window for volatility/drawdown/Sharpe and implies risk_free_rate_pct via 'Sharpe ratio', but leaves the required scheme_codes parameter (format, source, uniqueness) entirely undefined.

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 ('Compare ... mutual funds side by side') and quantifies the scope (1 to 5). The multi-fund framing implicitly distinguishes it from single-fund siblings like get_scheme_quote and get_scheme_details, but no sibling is named explicitly.

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 'side by side' phrasing implies the comparison use case, and the return list hints at what you get instead of single-fund data. However, there is no explicit when-to-use/when-not, no mention of the alternative single-fund tools, and no prerequisite such as obtaining scheme codes from search_schemes first.

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