jules_get_sessionFetch session metadata, state, and outputs to check a coding task's progress and final results.
Fetch session metadata, state, and outputs
| Name | Required | Description | Default |
|---|---|---|---|
| session_id | Yes | The Jules session ID |
Changes observed during successful MCP inspections.
v1.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is established. The description adds that the tool returns metadata, state, and outputs, but does not disclose potential errors, access requirements, or whether the 'outputs' are full transcripts or summaries. No contradiction exists.
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?
The description is a single, compact, front-loaded sentence with no fluff. Every word helps the agent understand what the tool does.
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 simple read-only getter with one parameter and no output schema, the description adequately conveys the return categories. It is sufficient for an agent to call the tool correctly, though a brief note about what 'outputs' contains would make it fully self-sufficient.
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 sole parameter session_id is already described as 'The Jules session ID'. The description adds no further meaning to the parameter beyond what the schema 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?
The description specifies a clear verb, 'Fetch', and a specific resource, 'session', while enumerating the kind of data it returns: metadata, state, and outputs. This is distinct from listing sessions or fetching activities, though it could have explicitly disambiguated against 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?
No explicit guidance is given about when to use this tool versus the many sibling tools. The singular 'session' implies a single-session lookup, but alternatives such as jules_list_sessions or jules_get_activity are never mentioned, leaving selection to inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.