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

Annotations only declare destructiveHint=false; the description adds a meaningful behavioral constraint ('a source belongs to at most one case') that clarifies cardinality/uniqueness. It does not cover permissions, error/conflict behavior, or reversibility, so it adds some value but not rich behavioral context.

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?

Three short sentences, front-loaded with the action and scope, then the key parameter format, then the uniqueness rule. Every sentence carries distinct, non-redundant information.

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 no output schema and sparse annotations, the description covers the essential non-obvious details (source_key format, same-project requirement, one-case constraint). It omits auth/error handling, but for a link operation with 4 required params this is largely 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 0% across 4 params, so the description must compensate. It usefully explains source_key format (ToDo id or repository_id:issue_number), but leaves project_id, case_id, and the source_type enum undocumented, only partially filling the gap.

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 (Link) and resources (existing shared ToDo or synced GitHub Issue to a case), which clearly separates it from siblings like unlink_shared_work_case_source and create_shared_work_case. An agent can identify the operation 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?

Provides clear context: the source must already exist and live in the same shared project, and a source belongs to at most one case. It does not explicitly name alternatives (e.g., unlink_shared_work_case_source) or state when-not-to-use, but the prerequisite conditions are well conveyed.

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