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

Beyond the readOnly/idempotent annotations, it discloses the access-control model, the two projection modes and their precondition logic (resume needs the exact open obligationId; closed result derives the sole exact completed obligation and requires three converging conditions), operator exclusions, and an important caveat that neither projection proves settlement or money movement.

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?

Front-loaded with the core action and result fields before the projection detail. The projection sentences are dense and jargon-heavy, but for a tool with two special modes and an access model, each clause carries load and nothing is pure 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?

With no output schema, the description itself enumerates the returned content and flags the projection caveats. For a 4-parameter read tool with an access model and two opt-in modes, an agent has everything needed to call it correctly.

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 conditional semantics the schema only hints at: which projection requires obligationId, which accepts none, and that the projection path is external-connector only. That is real added meaning over the property descriptions.

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+resource ('Get full detail of a single coordination thread') and enumerates the payload (subject, messages, attachments, participants, next owner, closeout state), which cleanly separates it from summarize_coordination_thread, list_my_coordination_threads, and find_coordination_threads.

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?

Explicitly scopes who may use it (household member or active participant/watcher) and who is excluded (managed-program operators, scoped specialists), plus the conditions under which each projection applies. It stops short of explicitly routing to summarize_coordination_thread for a lighter read, so it is clear context rather than full when/when-not guidance.

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