fpl_game_rules

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint. The description adds behavioral nuance: it works without a key, but FPL_SESSION_COOKIE unlocks more, and it details the return structure. This goes beyond what annotations provide, though less critical since annotations cover safety.

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 informative but compact, with a clear first sentence, a structured return format example, and a note on auth. Each part serves a purpose, though the return example is verbose – acceptable because it doubles as documentation.

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?

There is no output schema, so the description must explain the return values; it does so thoroughly, including a breakdown of element_types and total_players meaning. It also covers authentication. This is complete for a zero-param read-only tool.

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 baseline is 4. The description no parameter semantics needed. It focuses on return content, which is appropriate and aligns with the schema.

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 what the tool does: it returns lookup tables for positions, chips, phases, and scoring settings. It explicitly distinguishes this tool as the reference for IDs used by other tools, which sets it apart from sibling tools that provide data itself.

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 explains that this tool provides the lookup tables that other tools' ids refer to, and gives a concrete example (element_types resolves element_type id). This gives clear context for when to use it, but does not name specific alternative tools or exclusions.

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