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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety bar is low. The description still earns credit by disclosing a non-obvious behavioral fact: instruction bodies are bootstrapped via open_workspace text and are deliberately absent from the Workspace object, which prevents a wrong assumption that this call returns full instructions.

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?

Purpose and contents are front-loaded in the first two sentences, with the lifecycle caveats following. The closing negative-space sentence is longer than needed and could be tightened, but each sentence does convey distinct information an agent would otherwise have to guess.

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 an output schema present, return-value explanation is unnecessary, and annotations cover the safety profile; the description supplies the missing conceptual context (where the workspace_id comes from, what the object holds and withholds). Only the lack of explicit routing for the excluded data categories keeps it from a 5.

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% and the single parameter already documents itself as 'Workspace id returned by open_workspace.' The description's statement about provenance largely restates that, adding lifecycle context rather than new syntax or format detail. Baseline 3 is appropriate when the schema carries the parameter semantics.

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 ('Reads') and resource ('project facts for a workspace_id'), then enumerates exactly what the returned Workspace holds: project root, platform, Git branch/worktree facts, instruction-file paths, and skill metadata. It also names open_workspace as the producer of the id, so the agent can place it relative to that sibling without opening either 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?

Establishes the precondition clearly: call this when you hold a workspace_id previously returned by open_workspace. The 'does not contain chat memory, commands, pending results, or conversational topic state' sentence steers the agent away from this tool for those needs. It stops short of naming the specific alternative tools for that excluded state, so not a full when/when-not/alternatives treatment.

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