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

Annotations already flag it as a non-read-only, destructive, idempotent write; the description adds genuinely new behavior: dates are recalculated as a side effect, existing link attributes are overwritten rather than duplicated, cycle links fail atomically with nothing saved, and write permission is required. Each of these is consistent with destructiveHint/idempotentHint and goes beyond them.

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 short sentences and a second paragraph, all front-loaded: what it does, the type vocabulary, lag semantics, then the overwrite/cycle/permission rules. Nothing is repeated from the title and no sentence is filler.

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 mutation tool with no output schema this is close to complete: side effects, atomicity, idempotent overwrite behavior and permissions are all stated. The remaining gaps are the lagMinutes precedence rule and the fact that predecessor/successor are identifiers while the prose never says what form they take.

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; the description does add real meaning by expanding the four enum letters (FS = finish-to-start, SS, FF, SF) and defaulting to FS, which the schema only lists as bare codes. However it says "Lag is in working days" while the schema also exposes lagMinutes that takes precedence over lagDays, so the description actually narrows and slightly misrepresents the lag inputs.

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?

"Creates a dependency between two tasks and recalculates the dates" gives a specific verb (creates), a specific resource (task dependency/link) and the immediate side effect. No sibling could be confused with this: unlink_tasks is the inverse, and update_task edits a single task.

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 covers the re-link case ("if the two tasks are already linked, the existing link's type and lag are replaced") and the failure case (a cycle-creating link is rejected), which tells an agent when invoking is safe versus pointless. It never names an explicit alternative tool or states a prerequisite beyond write permission, so it stops short of full when/when-not routing.

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