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

With no annotations, the description carries the burden of disclosing behavior. It mentions that the simulation uses 'the latest available NAV history in the dataset', providing some data freshness context. It also indicates the nature of outputs, but it does not explicitly state that the operation is non-mutating or clarify any side effects. This is adequate but not detailed.

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 highly concise, consisting of two short sentences that front-load the primary purpose and output. The 'Data freshness' clause adds useful behavioral context without unnecessary verbosity. Every sentence earns its place.

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 complexity of a simulation tool with six parameters, a similar sibling tool, and an output schema, the description is too sparse. It does not explain the meaning of scheme_code (UPF/PPF/DPF), the role of optional filters, or how this tool relates to simulate_bulgarian_pension_saver_outcome. The description leaves critical gaps for an agent to select and invoke the tool correctly.

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 input schema has six parameters with 0% description coverage, and the tool description does not explain any of them. It mentions 'periodic contributions' but does not define required parameters like scheme_code or monthly_contribution, nor optional ones like fund_id, manager_slug, start_date, or end_date. The description fails to compensate for the complete lack of schema parameter documentation.

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 clearly states a specific action ('Simulate saver outcomes with periodic contributions into Bulgarian pension funds') and the outputs ('invested amount, terminal value, and IRR-like performance diagnostics'). It distinguishes the tool's core function, though it does not explicitly differentiate from the similarly named sibling 'simulate_bulgarian_pension_saver_outcome', preventing a top score.

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?

There is no guidance on when to use this tool versus alternatives. The description does not mention exclusions, prerequisites, or why one would choose this over the sibling tool. It only provides a generic simulation context, leaving usage entirely implied.

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