ppsspp_read16

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

No annotations are provided, so the description bears full burden. It explicitly states 'No side effects — pure read', explains endianness ('PSP is little-endian'), and mentions error condition ('Returns an error if address+2 exceeds the valid memory region'). This fully discloses behavior.

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 exceptionally well-structured with labeled sections (PURPOSE, USAGE, BEHAVIOR, RETURNS). Every sentence is informative and earns its place. No redundancy or filler.

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?

The description fully covers purpose, usage, behavior (including endianness and side effects), error handling, and return format. For a simple read tool with one parameter, this is complete and leaves no gaps.

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 100%, but the description adds valuable context to the 'address' parameter, explaining PSP memory layout (user RAM, kernel RAM, VRAM, etc.) and acceptable address formats. This adds meaning beyond the basic schema description.

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 an unsigned 16-bit little-endian value from PSP memory (specific verb and resource). It explicitly distinguishes from sibling tools ppsspp_read8, ppsspp_read32, and ppsspp_read_range, providing clear differentiation.

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 USAGE section explicitly states when to use this tool ('16-bit game-state fields') and when to use alternatives ('single bytes use ppsspp_read8; for 32-bit use ppsspp_read32; for arbitrary byte spans use ppsspp_read_range'). No ambiguity.

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