PRISM preflight

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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds crucial behavioral details beyond these: 'Deterministic and offline', 'reads packaged registry data only: no user-project files, no network, no credentials'. This tells the agent exactly what side effects (none) and data access patterns exist, providing significant added transparency without contradicting the annotations.

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?

Two sentences, each earning its place: the first states the core action and output, the second clarifies the safety and deterministic nature. No filler, no redundancy, and the most important information is front-loaded.

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 tool's simple complexity, the description is sufficiently complete. It defines the output (claim-packet contract) and the input context (task). It also mentions constraints (offline, no credentials) and implies the tool is meant for preflight planning before measurement. The presence of an output schema means the description does not need to detail return values. A minor gap is that it does not specify any prerequisites or expected input format, but this is not critical for a preflight helper.

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 schema has 0% description coverage, so the description carries the burden of explaining parameters. The description ties 'task' to the selection process and '3-5 useful perspectives' hints that max_perspectives controls the output count, but 'mode' is completely unexplained. It provides some semantic linkage but does not fully compensate for all three parameters, especially the mysterious 'mode' with a default of 'standard'.

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 uses specific verbs ('Select' and 'return') and names the concrete outputs: '3-5 useful perspectives' and 'the claim-packet contract'. This clearly differentiates from siblings like prism.measure (which likely executes measurements) and prism.synthesis_contract (which may define the contract format rather than select perspectives). The scope is explicitly bounded to a preflight role.

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 for when this tool is appropriate: it is deterministic, offline, and reads only packaged registry data, making it safe for preflight use without external dependencies. However, it does not explicitly state when to use it over siblings like prism.measure or prism.synthesis_contract, nor does it give exclusions ('use X instead'). The usage guidance is implicit rather than explicit, so it falls short of a 5.

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