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

Annotations only declare readOnlyHint=false and destructiveHint=false. The description goes further, disclosing the duplicate-guide failure mode and the cross-product visibility behavior ('Core does not show the guide. Live reads it on the project'), which the agent cannot infer from structured fields. Missing detail on permissions or return behavior keeps it short of a 5.

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?

Dense but front-loaded: purpose first, then payload structure, then failure/routing, then visibility. Every sentence carries a distinct fact, though the parameter enumeration sentence is somewhat packed.

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 4-param mutation tool with no output schema and minimal annotations, the description covers the key runtime facts an agent needs: structured payload shape, minimum block requirement, duplicate failure, and downstream visibility. Adequate without being exhaustive.

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%, so the baseline is 3, but the description adds real value beyond the schema: it enforces 'structured fields, not markdown' and adds the constraint 'at least one block with a title' plus the nested question shape (text/note/key), which the schema documents but does not emphasize as a call-shaping rule.

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 specific verb and resource ('Create the first interview guide on a project') and explicitly scopes it to the first guide, immediately separating it from guides_edit. An agent can identify the operation and its uniqueness constraint without opening the schema.

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?

Gives explicit when-to-use ('Use this to upload a new guide') and names the alternative with the selecting condition ('Fails if the project already has a guide — then use guides_edit'). Routing is unambiguous.

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