whodb_platform_source_fields

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

Annotations already declare readOnlyHint/idempotentHint/openWorldHint, but the description adds genuine value: 'does not expose credentials' (a security-relevant disclosure) and 'without changing defaults' for the workspace override. Output schema exists, so return format isn't needed. Minor repetition of read-only, but the credential note earns the score.

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, then when-to-use, then safety, then parameter guidance. Every sentence carries information; the 'Prefer fields such as...' sentence is slightly dense but functional rather than padding.

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 an output schema present, the description needn't explain return values, and it adequately covers purpose, timing, safety, and the workspace override. Completeness would be 5 only if it pointed to the sibling that supplies the source_type value.

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% (baseline 3), and the description goes beyond it by recommending a concrete projection set, ["Key", "Kind", "Required", "LabelKey"], and explaining that the workspace object is per-call targeting that does not mutate defaults. That is meaningful guidance not present in the schema text alone.

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 and resource ('List connection fields') scoped to 'one hosted WhoDB source type', which cleanly separates it from sibling whodb_platform_source_types (which enumerates types rather than their fields). An agent can distinguish it without opening the 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?

Gives explicit when-to-use context: 'before source creation or draft connection tests to discover required fields and defaults.' It also clarifies the workspace targeting behavior. It stops short of naming the exact sibling (e.g., source_types to get the type, source_create to consume the fields), so it's clear but not exhaustive.

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