get_save_game_slot_info

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new behavioral context: a missing slot yields exists=false with an error field rather than a failure, the save_path format is disclosed, and file_size/modified fields are conditional on the file being on disk. It stops short of noting any rate/permission detail, but that is minor.

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?

Front-loaded with the core purpose, followed by a compact Returns block. Since there is no output schema, that return enumeration earns its place. Slightly dense with parenthetical detail but no wasted sentences.

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 no output schema, the description carries the burden of return-shape documentation and does so completely, plus covers the missing-slot edge case. Only the absence of any sibling-routing guidance keeps it from being fully complete for an agent choosing among save-game tools.

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 100%, so both slot_name and user_index (including the note that desktop saves ignore user_index) are already documented in the schema. The description implies slot_name via '<slot>.sav' but adds no syntax beyond what the schema provides, so the baseline 3 applies.

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 ('Read') and resource ('metadata of a save slot'), then enumerates exactly which fields (save_path, file_size, modified_iso, modified_ticks) it returns. This lets an agent distinguish it from siblings like does_save_game_exist (boolean only) and get_save_game_info without opening any schema.

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 clarifies the missing-slot behavior (exists=false, not a failure), which is useful context for deciding to call it. However, it never names an alternative (does_save_game_exist, get_save_game_info, list_save_games) or states the condition under which this tool should be preferred, so selection vs siblings remains implicit.

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