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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds real value beyond them: auth requirements per transport ("Hosted requires bearer...; stdio checks local project binding"), the WORKSPACE_KEY_REQUIRED error condition, and the guarantee that no money is spent. Minor gap: no disclosure of latency or rate-limit behavior.

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-loads the core purpose in the opening clause and each subsequent sentence carries distinct information (alternatives, side-effect guarantees, auth modes, error code). It is dense with semicolon-joined clauses and slightly run-on, but there is little waste.

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?

An output schema exists, so return values need not be described, yet the description states the return scope anyway as light reinforcement. Auth requirements, error conditions, and negative scope are all covered, leaving only minor unexplored traits (e.g., behavior when refresh fails over the network).

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 100% and the single refresh parameter is fully documented in the schema, including its stdio-only scope. The description adds nothing about parameter semantics beyond what the schema already provides, so the baseline 3 is appropriate.

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 and resource ("Check workspace/session authentication and readiness, plus common setup errors") and explicitly scopes what it does not do ("Does not execute capabilities or spend money"). It also distinguishes itself from hydracept_job_status and hydracept_capabilities by name, so an agent can route without opening a 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?

Gives an explicit trigger ("Use when setup, auth, or project binding is in doubt"), names the sibling to use instead for executions ("use hydracept_job_status for a specific execution"), and rules out a near-neighbor ("Not a substitute for hydracept_capabilities"). When-to-use, when-not, and alternatives are all present.

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