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

The annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world scope, so the safety profile is covered. The description adds useful corpus scope (what content is searchable) and the shape of returned fields, but says nothing about ranking, pagination of the result set, or behavior on zero matches. With annotations carrying safety, a 3 is appropriate.

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 dense sentences, front-loaded with the verb and resource, then the corpus contents and return shape. No filler or redundant restatement of the title.

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 and rich annotations, the description need not explain return values in depth; it covers purpose, corpus, and result fields. The only real gap is routing guidance relative to the sibling tools, which is minor for a low-complexity two-parameter search.

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 description coverage is 100% — query and limit are both documented in the schema, so baseline 3 applies. The description mentions no query syntax, matching behavior, or how limit interacts with results, so it adds nothing beyond the schema.

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 ('Keyword search') and resource ('the Founder Ventures library'), and enumerates the corpus types (growth playbooks, PLG glossary, case studies, tool comparisons, research). It does not explicitly contrast itself with siblings read_founder_ventures_page or list_founder_events, so the distinction is inferable rather than stated.

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?

Usage is implied: 'keyword search' suggests this is the discovery/entry tool versus reading a specific page, but there is no explicit 'use this when…' or 'for X use Y instead' guidance. With three plausible siblings and no routing instructions, the agent must infer the boundary.

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