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

Annotations already provide readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds meaningful context about the content scope (2,000+ symbols, categories like animals, scenarios, people) and the search/filter behaviors, which helps set expectations beyond the annotations. It does not discuss pagination or response format, but for a read-only list tool, that is acceptable given annotation coverage.

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 description is front-loaded with the primary purpose and then provides illustrative examples that add context. It is somewhat lengthy (about 60 words) but well-organized, and each sentence serves a purpose—listing categories and usage modes. It is efficient without being terse or redundant.

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 read-only list/search tool with 5 fully documented parameters and no output schema, the description adequately covers the domain and usage context. It does not detail pagination or response shape, but the schema covers those parameters, and the examples give a good sense of what the tool returns. The description is complete enough for an agent to select and invoke the 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 description coverage is 100%, with each parameter (q, limit, letter, offset, compact) fully documented in the schema. The description mentions 'q' and 'letter' but adds no new meaning; it simply restates 'search by keyword' and 'Filter by starting letter.' Since the schema carries the parameter documentation, the baseline of 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 clearly states the tool's function with specific verbs: 'Browse and search our complete dream interpretation dictionary containing 2,000+ dream symbols.' It explicitly describes filtering by letter and searching by keyword, and the resource (dream symbols) is unambiguous. It naturally distinguishes from siblings like get_dreams_symbols_id (single symbol) and get_dreams_symbols_random (random symbol) by emphasizing the complete dictionary and list/search capabilities.

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?

The description implies usage: 'Filter by starting letter for A-Z navigation or search by keyword' tells the user when to use this tool for browsing/searching. However, it does not explicitly mention alternatives or exclusions (e.g., 'for a specific symbol, use get_dreams_symbols_id'). There is no direct when/when-not guidance, so the recommendation is only implied.

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