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

With readOnlyHint=true and destructiveHint=false already present, the description adds meaningful context beyond the annotations: the attributions are a 'documented school split rather than a fixed table' and 'the response echoes which one produced the answer.' This explains the flexible nature of the data and the echo behavior, which an agent would not infer from schema alone.

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 two sentences and front-loads the core return payload before moving to the school-split nuance and intended use cases. Every sentence earns its place; it could be slightly tighter but is not bloated or repetitive.

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?

Given there is no output schema, the description compensates by enumerating the returned fields and noting that the response echoes the chosen reading. Combined with 100% parameter schema coverage and read-only annotations, an agent has enough context to invoke the tool correctly, though a brief note on the response envelope would make it fully complete.

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%, so the schema already fully documents all three parameters, including enums, defaults, and the compact format behavior. The description adds only a high-level reference to 'the requested reading' without supplementing the schema's parameter details, so the baseline score of 3 is appropriate.

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 opens with a specific verb and resource: 'Return all 22 Hebrew letters' and enumerates exactly which attributes are included (numeric value, final form, class, element/planet/sign, tarot trump, path number). This clearly distinguishes it from sibling get_kabbalah_letters_id, which targets a single letter, by emphasizing 'all 22.'

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 gives explicit use cases: 'letter reference pages, tarot apps that render the paths, and any feature that has to say what a letter carries and on whose authority.' It does not explicitly name alternative tools or state when not to use it, but the 'all 22' scope strongly implies the contrast with a single-letter endpoint.

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