player_balances

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

With no annotations provided, the description carries the full burden of behavioral disclosure, and it does so thoroughly. It discloses that no balances are totalled or converted, that it makes one logical GET request, does not auto-fetch continuation pages, that array responses are locally limited to 100 rows and 256 KiB with truncation reported, and that oversized records are refused without partial fields. This is exceptional transparency for a read tool.

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 dense but well-structured, front-loading the core purpose and then adding behavioral caveats. Every sentence adds information, but the density of caveats (truncation, refusal, forwarding filters) makes it slightly harder to parse than necessary. Still, it earns its length by covering critical operational details.

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?

For a read tool with no output schema and no annotations, the description is remarkably complete. It covers input semantics, request behavior, pagination, response limits, truncation reporting, and error handling for oversized records. An agent has everything needed to call this tool correctly and interpret its results.

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 description coverage is 0%, so the description must compensate for the schema's lack of parameter documentation. It explains that 'players' is a comma-separated list selector, 'token_type' is an upstream filter, and that other declared filters are forwarded as supplied without implying effectiveness. This adds meaningful semantics beyond the bare schema, though it doesn't detail the exact format of 'username' or provide examples.

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 the tool reads current token balances for explicitly supplied players, with a specific verb ('Read'), resource ('token balances'), and scope ('explicitly supplied players'). It distinguishes itself from siblings like player_archived_balances and player_unclaimed_balances by focusing on current balances and explicitly supplied players.

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 provides clear context on when to use this tool: when you have explicit player identifiers and need current token balances. It notes that the players selector can be a comma-separated list and that token_type is an upstream filter. However, it doesn't explicitly name alternative tools for different scenarios (e.g., archived balances, unclaimed balances), leaving some routing to inference.

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