Describe Public API Surface

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds substantial beyond-schema behavior: how property accessors, consts, and enums render, that the type list is capped with the true total in the envelope, that it works on live AND recalled sessions, and honest "Known v1 simplifications" about accessibility computation and modifier-omitted types.

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 purpose is front-loaded in the first sentence, and most sentences carry load-bearing detail. However, the volume is high for a 4-param read-only tool, with heavy ALL-CAPS emphasis and stacked parentheticals that reduce scannability and add redundancy (accessibility/rendering rules are stated twice).

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 return-shape burden and does so well: it explains declarations are compact signatures, that member lists are whole while types are capped, and that the envelope carries the true total. Combined with the simplification caveats, an agent has everything needed to call and interpret it correctly.

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%, so the baseline is 3, but the description adds real semantics the schema lacks: includeInternal surfaces the internal/private-protected family, and a namespace prefix matching no namespace yields a 'note' ahead of typesScanned 0. It reinforces the defaults for scope and includeTests rather than merely restating them.

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 first sentence names a specific verb ("List") and resource ("PUBLIC API SURFACE of a solution or namespace") and immediately clarifies scope (externally-visible types with their members). It differentiates itself from siblings by naming compare_with_previous and diff_public_contract, plus the "public-API digest, not a firehose" framing that separates it from a full-documentation tool.

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?

It gives explicit use cases ("review a public contract before changing it, or as the baseline for a contract comparison") and names the chaining alternatives (save_session then compare_with_previous, or diff_public_contract, noting the latter is outside the default profile). It does not state an explicit when-not condition beyond the firehose contrast, so it falls just 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.