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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the write/non-destructive safety profile is covered structurally. The description adds meaningful framing (this is the intent layer tasks are measured against) but does not disclose the merge-vs-replace semantics or what happens to unspecified fields - those live only in the schema.

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 front-loaded sentences with a clear purpose statement, an importance rationale, and an update trigger; the trailing API reference is compact. No wasted text, though the middle sentence is more motivational than operational.

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 an 8-parameter write tool with 50% schema coverage and no output schema, the description should say more about replace-vs-merge behavior and the expected result. It covers the conceptual role of the fields but leaves meaningful gaps an agent would want before invoking it.

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 only 50%, so half the parameters (client, project, client_id, project_id) carry no documentation in either place. The description gestures at facts and reference links, which loosely maps to the facts and add_links parameters, but adds no syntax or format detail beyond what the schema already states.

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 uses a specific verb (write/update) and names the resource and its three components: the shared project brief, structured facts, and reference links. This is clear and concrete, but it never distinguishes itself from closely related siblings such as update_client_context or log_project_decision, so an agent must infer which context tool applies.

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?

It gives a clear trigger condition - 'keep it current when the goal or ground rules change' - which tells the agent when this tool is appropriate. It stops short of naming alternative tools or exclusion conditions (e.g., per-field updates vs. full brief replacement).

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