save_context

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

With no annotations, the description must carry the full behavioral burden. It usefully discloses that saved context 'persists across sessions and editors' and that calling proactively matters. However, it says nothing about overwrite/deduplication behavior, whether saves are keyed by type, permissions, or what a save returns — notable gaps for a mutation tool with no annotations.

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 tight sentences, front-loaded with the core action, then usage triggers, then the persistence rationale. No filler; every clause earns its place.

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 a four-parameter write tool with no output schema and no annotations, the description covers what it does, when to call it, and the cross-session persistence guarantee. It is nearly complete, missing only the post-save mechanics (what happens to existing context, what is returned).

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%, so the schema already documents all four parameters including the enum mappings and an inline example. The description's prose enumeration of the context types mirrors the enum rather than extending it, so baseline 3 applies.

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: 'Save context to persistent memory.' The write-side counterpart to siblings like get_context is obvious from the verb, though the description never names a sibling to sharpen the boundary. Purpose is unambiguous and distinct from the read/summary siblings.

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 concrete, enumerated triggers — decisions, non-obvious discoveries, agreed constraints, WIP state, coding preferences — plus an explicit 'call proactively' directive. It lacks any 'when not to use' guidance or a pointer to the retrieval sibling (get_context), so it stops short of full routing guidance.

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