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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior, and the description agrees with them. Beyond that, it adds two decision-critical disclosures: only public profiles are returned, and private profiles are indistinguishable from nonexistent ones — preventing the agent from concluding an investor doesn't exist from a not-found result. It also flags the non-obvious trait that the response includes similar investors.

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?

Three sentences, each earning its place: scope plus return enumeration, parameter provenance, and the private-profile caveat. The most decision-relevant clause is front-loaded, and no sentence repeats annotation or schema content.

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 one fully documented parameter and rich annotations, the main gap is the missing output schema, which the description compensates for by exhaustively enumerating the response fields. The login-source routing and the private-vs-nonexistent caveat round out everything an agent needs to select and invoke this tool 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%, and the schema already documents the login parameter including the optional leading '@'. The description adds value above the baseline by stating where valid login values come from (sibling search/list tools or a signed.com URL), which prevents the agent from fabricating or guessing logins.

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 precise verb-resource pair — fetching one investor's public Signed profile by login — and enumerates the returned content (bio, sectors, check size, pinned portfolio companies, pitch preferences, follower counts, similar investors). This scoping clearly distinguishes it from sibling tools that enumerate or search collections rather than retrieve a single profile.

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?

Provides explicit workflow guidance by naming the login sources: search_investors, list_investors, or a signed.com/@login URL. However, it lacks an explicit 'use this instead of X when Y' exclusion against close siblings like list_investor_followers, so the contextual guidance is clear but not fully formalized.

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