Update a goal

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

Beyond annotations (readOnlyHint false, idempotentHint true), the description discloses critical behavior: it writes, it cannot set loggedHours because those come from time entries, there is no archived status, and CLIs are needed for deletion. It also explains the partial-update expectation with 'Only send the fields that should change,' which is not derivable from the schema or annotations 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 compact yet information-dense. Every sentence adds value: the opening line states purpose, then exclusions, status semantics, deletion guidance, and usage instruction. No filler or redundancy; it is well-structured with the core purpose front-loaded.

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?

Despite lacking an output schema, the description covers all operational aspects needed to invoke the tool correctly: what it updates, what it cannot update, how to handle related behaviors (logged hours, shelving, deletion), and the PATCH-like calling convention. The only minor gap is the return value, but the annotations and sibling context make this a complete picture for an agent.

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 schema fully describes each parameter. The description adds meaningful usage context by explaining that loggedHours is deliberately absent and instructs to send only changed fields, which clarifies partial-update semantics. This goes beyond what the schema states about optionality, though it doesn't add per-parameter details.

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 states exactly what the tool does: 'Updates fields on an existing goal, including its status.' This is a specific verb and resource that clearly separates it from sibling tools like create_goal or update_task. It also explicitly notes what it does not do (loggedHours, deleting), further sharpening purpose.

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 guidance on when not to use this tool and directs to alternatives: logged hours must be changed via log_time, and deletion is not available as a tool (tell the user to use the CLI). It also clarifies status semantics (no archived, PAUSED for shelving), which helps the agent decide when this tool is appropriate.

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