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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false). The description adds real context beyond them: results are limited to 'public details' for 'verified active' investors, and the instruction to 'Preserve returned URLs exactly' signals URLs are fragile/high-value. It does not describe error behavior or result shape, but the output schema covers returns.

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, zero filler. The core purpose is front-loaded and the URL-preservation caveat is placed second, where it is easy to catch before calling.

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?

For a single-parameter read tool with an output schema and full annotation coverage, the description supplies scope, key, and a caveat, so an agent has what it needs to invoke it. The only minor gap is that it does not state the failure mode for slugs that are not verified/active.

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?

With one parameter at 100% schema description coverage, the schema already defines slug and its provenance. The description only restates the key ('by slug'), adding no format or validation detail beyond the schema, so the baseline 3 applies.

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 gives a specific verb (get), resource (investor details and funding activity), scope (one verified active AI investor), and key (by slug). It is immediately distinguishable from search_investors and the other get_* siblings by naming the entity and the single-item lookup mode.

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?

'By slug' plus the schema's note that the slug comes from search_investors implies the search-then-fetch workflow, and 'verified active' hints at a coverage limit. However, the description never explicitly states when to use this versus search_investors or what happens for an unverified/inactive slug, so guidance is implied rather than stated.

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